Hi all,
Sort of OT, but my truck, being a 1990 is still made of metal. And
lacking a NG called rec.crafts.metalNOTworking, I thought I might try
here. I also posted to alt.autos.for.pickups, but I almost always get
most excellent advice from RCM.

Anyhow...

I have a 1990 F150 XLT, 2WD, auto trans, 5.0L EFI, A/C, dual fuel
tanks. About 90K miles on the (2nd) engine. In the last week or so, I
have had a really intermittent problem. When driving at a steady speed
maybe 40-50 mph, the engine would "stumble" almost like it was cutting
out for just a second. It would do this 2 or 3 times, then run fine.
Otherwise, it ran smooth as can be. No "check engine" light. A couple
of days ago, this seemed to progress to happening more often and also
sometimes running very rough at idle, almost like it was trying to
idle way too slowly. Yesterday it got worse, and now will barely idle.
If I do not constantly work the gas pedal, it will stall (in or out of
gear). Now I am getting a check engine light, which goes out once the
speed gets up high enough for it to keep running. Once you are moving,
it runs fine.

I checked the really simple stuff, air filters, plugs, cap, rotor,
ignition wires, no wires knocked off of sensors, etc. None of that
changed anything. This has the "feel" (whatever that means) of a fuel
delivery problem, but I have no solid reason for saying that. I am an
OK backyard mechanic, but a slightly stupid as to how to diagnose EFI
type problems, or maybe even how to narrow it down.

Any thoughts on anything else to try before I (GASP!) relent and drop
it with my mechanic?

I appreciate any and all suggestions.
Thanks very much,
AL A.

Al A. wrote:
Hi all,
Sort of OT, but my truck, being a 1990 is still made of metal. And
lacking a NG called rec.crafts.metalNOTworking, I thought I might try
here. I also posted to alt.autos.for.pickups, but I almost always get
most excellent advice from RCM.

Anyhow...

I have a 1990 F150 XLT, 2WD, auto trans, 5.0L EFI, A/C, dual fuel
tanks. About 90K miles on the (2nd) engine. In the last week or so, I
have had a really intermittent problem. When driving at a steady speed
maybe 40-50 mph, the engine would "stumble" almost like it was cutting
out for just a second. It would do this 2 or 3 times, then run fine.
Otherwise, it ran smooth as can be. No "check engine" light. A couple
of days ago, this seemed to progress to happening more often and also
sometimes running very rough at idle, almost like it was trying to
idle way too slowly. Yesterday it got worse, and now will barely idle.
If I do not constantly work the gas pedal, it will stall (in or out of
gear). Now I am getting a check engine light, which goes out once the
speed gets up high enough for it to keep running. Once you are moving,
it runs fine.

I checked the really simple stuff, air filters, plugs, cap, rotor,
ignition wires, no wires knocked off of sensors, etc. None of that
changed anything. This has the "feel" (whatever that means) of a fuel
delivery problem, but I have no solid reason for saying that. I am an
OK backyard mechanic, but a slightly stupid as to how to diagnose EFI
type problems, or maybe even how to narrow it down.

Any thoughts on anything else to try before I (GASP!) relent and drop
it with my mechanic?

Fuel filter?
Water/bad fuel in the gas tank?

"Jim Stewart" wrote in message
...
Al A. wrote:
Hi all,
Sort of OT, but my truck, being a 1990 is still made of metal. And
lacking a NG called rec.crafts.metalNOTworking, I thought I might try
here. I also posted to alt.autos.for.pickups, but I almost always get
most excellent advice from RCM.

Anyhow...

I have a 1990 F150 XLT, 2WD, auto trans, 5.0L EFI, A/C, dual fuel
tanks. About 90K miles on the (2nd) engine. In the last week or so, I
have had a really intermittent problem. When driving at a steady speed
maybe 40-50 mph, the engine would "stumble" almost like it was cutting
out for just a second. It would do this 2 or 3 times, then run fine.
Otherwise, it ran smooth as can be. No "check engine" light. A couple
of days ago, this seemed to progress to happening more often and also
sometimes running very rough at idle, almost like it was trying to
idle way too slowly. Yesterday it got worse, and now will barely idle.
If I do not constantly work the gas pedal, it will stall (in or out of
gear). Now I am getting a check engine light, which goes out once the
speed gets up high enough for it to keep running. Once you are moving,
it runs fine.

I checked the really simple stuff, air filters, plugs, cap, rotor,
ignition wires, no wires knocked off of sensors, etc. None of that
changed anything. This has the "feel" (whatever that means) of a fuel
delivery problem, but I have no solid reason for saying that. I am an
OK backyard mechanic, but a slightly stupid as to how to diagnose EFI
type problems, or maybe even how to narrow it down.

Any thoughts on anything else to try before I (GASP!) relent and drop
it with my mechanic?

Fuel filter?
Water/bad fuel in the gas tank?

does it have an idle air controller solenoid? i had a vette with those
symptoms that changing this fixed.

In article , Al A. says...

I checked the really simple stuff, air filters, plugs, cap, rotor,
ignition wires, no wires knocked off of sensors, etc. None of that
changed anything.

If this engine has a plastic snorkel between the mass flow air
sensor and the throttle body, check to see if it has developed
any cracks or leaks at the joints or along its length, if it's
convoluted.

An air leak there will cause similar problems.

Jim


--
==================================================
please reply to:
JRR(zero) at pkmfgvm4 (dot) vnet (dot) ibm (dot) com
==================================================

Carbureted?

Run it for a few minutes without the air filter. If it runs clean and the air
filter is filthy then replace the air filter.

The PCV valve may be completely clogged.

You may have a plugged fuel filter or (worse) a plugged fuel line.

Suggest you remove your air cleaner assembly and open the choke in your
carburetor and have a look down in there. Pump the gas using the lever on the
side, is the accelerator pump working?

If it's fuel injected, take it in and have the mechanic put it on his Motronic
machine.

If you have the service manual, it may have a diagnostic tree for this problem.
If you don't have the service manual, it may be available inexpensively in CD
form on ebay.

Oh, just saw the bit about the check engine light. Not good!

GWE

Al A. wrote:

Hi all,
Sort of OT, but my truck, being a 1990 is still made of metal. And
lacking a NG called rec.crafts.metalNOTworking, I thought I might try
here. I also posted to alt.autos.for.pickups, but I almost always get
most excellent advice from RCM.

Anyhow...

I have a 1990 F150 XLT, 2WD, auto trans, 5.0L EFI, A/C, dual fuel
tanks. About 90K miles on the (2nd) engine. In the last week or so, I
have had a really intermittent problem. When driving at a steady speed
maybe 40-50 mph, the engine would "stumble" almost like it was cutting
out for just a second. It would do this 2 or 3 times, then run fine.
Otherwise, it ran smooth as can be. No "check engine" light. A couple
of days ago, this seemed to progress to happening more often and also
sometimes running very rough at idle, almost like it was trying to
idle way too slowly. Yesterday it got worse, and now will barely idle.
If I do not constantly work the gas pedal, it will stall (in or out of
gear). Now I am getting a check engine light, which goes out once the
speed gets up high enough for it to keep running. Once you are moving,
it runs fine.

I checked the really simple stuff, air filters, plugs, cap, rotor,
ignition wires, no wires knocked off of sensors, etc. None of that
changed anything. This has the "feel" (whatever that means) of a fuel
delivery problem, but I have no solid reason for saying that. I am an
OK backyard mechanic, but a slightly stupid as to how to diagnose EFI
type problems, or maybe even how to narrow it down.

Any thoughts on anything else to try before I (GASP!) relent and drop
it with my mechanic?

I appreciate any and all suggestions.
Thanks very much,
AL A.

There are a lot of things that could cause your problem. The first thing I
would do is go to your local parts store and get a code reader. They're
cheap (the last one I bought was like $19) and it'll translate the code(s)
that are causing the check engine light to go on. Most code readers come
with a book that'll tell you what the codes mean.

At that point you can make a decision about how to proceed. The code may
not be your problem, but may be as a result of your core problem and should
help with diagnoses. I've learned over the last few years that chasing a
problem on a car with an engine management system using the sensibilities
developed by working on simple old-timey cars with carburetors is a recipe
for frustration.

It's actually good that the engine light is on. Now you've got a consistent
problem that is traceable.

Peter
--

"Al A." wrote in message
...
Hi all,
Sort of OT, but my truck, being a 1990 is still made of metal. And
lacking a NG called rec.crafts.metalNOTworking, I thought I might try
here. I also posted to alt.autos.for.pickups, but I almost always get
most excellent advice from RCM.

Anyhow...

I have a 1990 F150 XLT, 2WD, auto trans, 5.0L EFI, A/C, dual fuel
tanks. About 90K miles on the (2nd) engine. In the last week or so, I
have had a really intermittent problem. When driving at a steady speed
maybe 40-50 mph, the engine would "stumble" almost like it was cutting
out for just a second. It would do this 2 or 3 times, then run fine.
Otherwise, it ran smooth as can be. No "check engine" light. A couple
of days ago, this seemed to progress to happening more often and also
sometimes running very rough at idle, almost like it was trying to
idle way too slowly. Yesterday it got worse, and now will barely idle.
If I do not constantly work the gas pedal, it will stall (in or out of
gear). Now I am getting a check engine light, which goes out once the
speed gets up high enough for it to keep running. Once you are moving,
it runs fine.

I checked the really simple stuff, air filters, plugs, cap, rotor,
ignition wires, no wires knocked off of sensors, etc. None of that
changed anything. This has the "feel" (whatever that means) of a fuel
delivery problem, but I have no solid reason for saying that. I am an
OK backyard mechanic, but a slightly stupid as to how to diagnose EFI
type problems, or maybe even how to narrow it down.

Any thoughts on anything else to try before I (GASP!) relent and drop
it with my mechanic?

I appreciate any and all suggestions.
Thanks very much,
AL A.

I checked the really simple stuff, air filters, plugs, cap, rotor,
ignition wires, no wires knocked off of sensors, etc. None of that
changed anything. This has the "feel" (whatever that means) of a fuel
delivery problem, but I have no solid reason for saying that.

Check all your vacuum lines, especially the two that go from
your egr tube to a little diecast metal sensor box. That's how the
computer knows the EGR is working, and if the hoses are leaking
or have come off, it will set the EGR wrong and it'll run rough. The
sensor itself isn't very expensive either, though on one of my trucks
I had to special order the EGR tube itself (rust). And lastly, the EGR
actuator can also go bad.

I suspect that the light keeps flashing on because the engine is
running too slow at that point.

--Glenn Lyford

I would replace the fuel filter first. Unless it is in the tank, it is
cheap and easy. And while I was Autozone picking it up, I would get them to
read the check engine light, which they do for free...

Had an '89 Ford truck that drove me crazy. Things to look for:
1. Sticking EGR. This one had an electronic sensor that would
illuminate the "check engine" light if it was not detecting proper
operation. An EGR stuck open will cause really rotten idle.
2. Bad exhaust gas oxygen sensor, though it should still idle OK.
3. Loose distributor; the timing gets retarded, performance and idle
both suffer.
4. Broken vacuum line from manifold to MAP sensor on right side of
firewall.
5. A corroded relay connection. Look on the left fender, forward near
the area above the headlight, and find a relay or two there. Thye get
salt/water spray, and electrolysys does the rest. Ignition gets weak
and intermittent.
You don't need a fancy machine to decode the check engine stuiff.
Get a Chilton manual for that truck, and it should have a diagram as to
where to stick a jumper wire to fire that light in sequenced flashes
that you count and look up the faults on a chart. Even better, buy a
Chevy :-)

Dan

Forgot to mention: Throttle position sensor goes bad, too.

Dan

Had a problem like this w/a Z71 Chevy. The catalytic converter was clogged
up.

Fuel filter.
Martin
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder



Al A. wrote:
Hi all,
Sort of OT, but my truck, being a 1990 is still made of metal. And
lacking a NG called rec.crafts.metalNOTworking, I thought I might try
here. I also posted to alt.autos.for.pickups, but I almost always get
most excellent advice from RCM.

Anyhow...

I have a 1990 F150 XLT, 2WD, auto trans, 5.0L EFI, A/C, dual fuel
tanks. About 90K miles on the (2nd) engine. In the last week or so, I
have had a really intermittent problem. When driving at a steady speed
maybe 40-50 mph, the engine would "stumble" almost like it was cutting
out for just a second. It would do this 2 or 3 times, then run fine.
Otherwise, it ran smooth as can be. No "check engine" light. A couple
of days ago, this seemed to progress to happening more often and also
sometimes running very rough at idle, almost like it was trying to
idle way too slowly. Yesterday it got worse, and now will barely idle.
If I do not constantly work the gas pedal, it will stall (in or out of
gear). Now I am getting a check engine light, which goes out once the
speed gets up high enough for it to keep running. Once you are moving,
it runs fine.

I checked the really simple stuff, air filters, plugs, cap, rotor,
ignition wires, no wires knocked off of sensors, etc. None of that
changed anything. This has the "feel" (whatever that means) of a fuel
delivery problem, but I have no solid reason for saying that. I am an
OK backyard mechanic, but a slightly stupid as to how to diagnose EFI
type problems, or maybe even how to narrow it down.

Any thoughts on anything else to try before I (GASP!) relent and drop
it with my mechanic?

I appreciate any and all suggestions.
Thanks very much,
AL A.

----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----

Thanks for all of the replies, guys! I've got my work cut out for
tomorrow afternoon, I guess. That is exactly what I was hoping for.

I did try an autozone to get the code read, but the one I was at only
had a reader for OBD2 systems, mine is too old for OBD2. Said that
they probably lost it!

I think I may have the dreaded fuel-filter-in-the tank, as i looked
but could not find an external one, but I am planning to look again
and ask my parts guy to check if he lists one. I have the same problem
running on either of my tanks, which as it happens, each have fuel
from a different gas station. So I am thinking bad fuel/water is
unlikely.

Checked for the loose distributor and the cracked air duct from the
air cleaner box (wasted 4 days on THAT problem a few years back with
another car. good call Jim!) This has the dual heavy rubber air hoses
that look like oversized radiator hose, rather than the corrigated
plastic duct.

I have to take a look at a manual to see how to get the code to read
out. There is another place around here that may do a freebie or
minimal cost code scan that is more likely to have a scanner that old.

Also have to take a closer look through all of the vacuum lines, etc.

And please Dan, don't get the whole Chevy/Ford war started here,
PLEASE!!

Thanks again for all of the info.

-AL A.

Al A. wrote:
Hi all,
Sort of OT, but my truck, being a 1990 is still made of metal. And
lacking a NG called rec.crafts.metalNOTworking, I thought I might try
here. I also posted to alt.autos.for.pickups, but I almost always get
most excellent advice from RCM.

Anyhow...

I have a 1990 F150 XLT, 2WD, auto trans, 5.0L EFI, A/C, dual fuel
tanks. About 90K miles on the (2nd) engine. In the last week or so, I
have had a really intermittent problem. When driving at a steady speed
maybe 40-50 mph, the engine would "stumble" almost like it was cutting
out for just a second. It would do this 2 or 3 times, then run fine.
Otherwise, it ran smooth as can be. No "check engine" light. A couple
of days ago, this seemed to progress to happening more often and also
sometimes running very rough at idle, almost like it was trying to
idle way too slowly. Yesterday it got worse, and now will barely idle.
If I do not constantly work the gas pedal, it will stall (in or out of
gear). Now I am getting a check engine light, which goes out once the
speed gets up high enough for it to keep running. Once you are moving,
it runs fine.

I checked the really simple stuff, air filters, plugs, cap, rotor,
ignition wires, no wires knocked off of sensors, etc. None of that
changed anything. This has the "feel" (whatever that means) of a fuel
delivery problem, but I have no solid reason for saying that. I am an
OK backyard mechanic, but a slightly stupid as to how to diagnose EFI
type problems, or maybe even how to narrow it down.

Any thoughts on anything else to try before I (GASP!) relent and drop
it with my mechanic?

I appreciate any and all suggestions.
Thanks very much,
AL A.

You didn't mention fuel filter. Have you changed it?

--
Gary Brady
Austin, TX
www.powdercoatoven.4t.com

"Al A." wrote in message
...
Hi all,
Sort of OT, but my truck, being a 1990 is still made of metal. And
lacking a NG called rec.crafts.metalNOTworking, I thought I might try
here. I also posted to alt.autos.for.pickups, but I almost always get
most excellent advice from RCM.

Anyhow...

I have a 1990 F150 XLT, 2WD, auto trans, 5.0L EFI, A/C, dual fuel
tanks. About 90K miles on the (2nd) engine. In the last week or so, I
have had a really intermittent problem. When driving at a steady speed
maybe 40-50 mph, the engine would "stumble" almost like it was cutting
out for just a second. It would do this 2 or 3 times, then run fine.
Otherwise, it ran smooth as can be. No "check engine" light. A couple
of days ago, this seemed to progress to happening more often and also
sometimes running very rough at idle, almost like it was trying to
idle way too slowly. Yesterday it got worse, and now will barely idle.
If I do not constantly work the gas pedal, it will stall (in or out of
gear). Now I am getting a check engine light, which goes out once the
speed gets up high enough for it to keep running. Once you are moving,
it runs fine.

I checked the really simple stuff, air filters, plugs, cap, rotor,
ignition wires, no wires knocked off of sensors, etc. None of that
changed anything. This has the "feel" (whatever that means) of a fuel
delivery problem, but I have no solid reason for saying that. I am an
OK backyard mechanic, but a slightly stupid as to how to diagnose EFI
type problems, or maybe even how to narrow it down.

Any thoughts on anything else to try before I (GASP!) relent and drop
it with my mechanic?

I appreciate any and all suggestions.
Thanks very much,
AL A.

Since it is a dual tank model, did you try to repeat the problem from each
tank, by switching the tank selector? There was a recall for those tanks'
fuel pumps. Do you know if the truck had the recall work done?

"Al A." wrote in message
...
Thanks for all of the replies, guys! I've got my work cut out for
tomorrow afternoon, I guess. That is exactly what I was hoping for.

I did try an autozone to get the code read, but the one I was at
only
had a reader for OBD2 systems, mine is too old for OBD2. Said that
they probably lost it!

I think I may have the dreaded fuel-filter-in-the tank, as i looked
but could not find an external one, but I am planning to look again
and ask my parts guy to check if he lists one. I have the same
problem
running on either of my tanks, which as it happens, each have fuel
from a different gas station. So I am thinking bad fuel/water is
unlikely.

Checked for the loose distributor and the cracked air duct from the
air cleaner box (wasted 4 days on THAT problem a few years back with
another car. good call Jim!) This has the dual heavy rubber air
hoses
that look like oversized radiator hose, rather than the corrigated
plastic duct.

I have to take a look at a manual to see how to get the code to
read
out. There is another place around here that may do a freebie or
minimal cost code scan that is more likely to have a scanner that
old.

Also have to take a closer look through all of the vacuum lines,
etc.

And please Dan, don't get the whole Chevy/Ford war started here,
PLEASE!!

Thanks again for all of the info.

-AL A

It's easy-you can read the codes with a cheapo VOM or a light bulb.
There's a self test connector under the hood. Any service manual will
tell you how to do it, but they may not have a list of all the codes.
I have one around somewhere...

In article ,
Al A. wrote:

I think I may have the dreaded fuel-filter-in-the tank, as i looked
but could not find an external one, but I am planning to look again
and ask my parts guy to check if he lists one. I have the same problem
running on either of my tanks, which as it happens, each have fuel
from a different gas station. So I am thinking bad fuel/water is
unlikely.

It's in a pain in the butt external location (IIRC), and you'll need the
damn stupid tool to get the hose off. Fuel pump is probably in the tank.
But rather than spin more wheels here, go to:

http://www.f150online.com/forums/forumdisplay.php?f=51

And ask a bunch of people with similar beasties, and experience with the
quirks of same.

--
Cats, coffee, chocolate...vices to live by

I think I may have the dreaded fuel-filter-in-the tank, as i looked
but could not find an external one, but I am planning to look again
and ask my parts guy to check if he lists one.

It's usually in the left frame rail right under the driver, it uses
special white U-shaped plastic clips to retain it, they just pull out
of the connector sideways with a screwdriver, then the hoses pull
out straight along the axis of the filter. Looks like a silver can,
maybe fist sized. Replacement filters usually have new clips, but
check to be sure before you break them in the process of getting
them out.

I have to take a look at a manual to see how to get the code to read
out.

I don't have it here, but it's two pins on the diagnostic connector,
then
get behind the wheel, turn the key, and count flashes. Then look up
numbers in book.

Wait a sec...try this:
http://www.therangerstation.com/tech_library/OBD_I.html
these guys have the pinouts AND the codes. I'm pretty sure
that the codes between the ranger and full size are the same, but
if not, I'm sure someone here will forcibly correct me. :^)

--Glenn Lyford

I have this same truck that I drive every day. As I recall from some
similar experience, several of the sensors were malfunctioning. The
EGR sensor was one of them and the other was the sensor that tells the
computer the engine temperature. The computer thought that the engine
was never warming up, so it ran it like it was always cold.
The truck seems to like Shell, Chevron or Exxon fuel the best.
I would say sensor problem first.

On Tue, 08 Nov 2005 16:42:13 -0500, Al A.
wrote:

Hi all,
Sort of OT, but my truck, being a 1990 is still made of metal. And
lacking a NG called rec.crafts.metalNOTworking, I thought I might try
here. I also posted to alt.autos.for.pickups, but I almost always get
most excellent advice from RCM.
I have a 1990 F150 XLT, 2WD, auto trans, 5.0L EFI, A/C, dual fuel
tanks. About 90K miles on the (2nd) engine.

wrote in message
ups.com...
I think I may have the dreaded fuel-filter-in-the tank, as i
looked
but could not find an external one, but I am planning to look
again
and ask my parts guy to check if he lists one.

It's usually in the left frame rail right under the driver, it uses
special white U-shaped plastic clips to retain it, they just pull
out
of the connector sideways with a screwdriver, then the hoses pull
out straight along the axis of the filter. Looks like a silver can,
maybe fist sized. Replacement filters usually have new clips, but
check to be sure before you break them in the process of getting
them out.

I have to take a look at a manual to see how to get the code to
read
out.

I don't have it here, but it's two pins on the diagnostic connector,
then
get behind the wheel, turn the key, and count flashes. Then look up
numbers in book.

Wait a sec...try this:
http://www.therangerstation.com/tech_library/OBD_I.html
these guys have the pinouts AND the codes. I'm pretty sure
that the codes between the ranger and full size are the same, but
if not, I'm sure someone here will forcibly correct me. :^)

--Glenn Lyford

Some will be different depending on engine size and type...

"Al A." wrote in message
...
Hi all,
Sort of OT, but my truck, being a 1990 is still made of metal. And
lacking a NG called rec.crafts.metalNOTworking, I thought I might
try
here. I also posted to alt.autos.for.pickups, but I almost always
get
most excellent advice from RCM.

Anyhow...

I have a 1990 F150 XLT, 2WD, auto trans, 5.0L EFI, A/C, dual fuel
tanks. About 90K miles on the (2nd) engine. In the last week or so,
I
have had a really intermittent problem. When driving at a steady
speed
maybe 40-50 mph, the engine would "stumble" almost like it was
cutting
out for just a second. It would do this 2 or 3 times, then run fine.
Otherwise, it ran smooth as can be. No "check engine" light. A
couple
of days ago, this seemed to progress to happening more often and
also
sometimes running very rough at idle, almost like it was trying to
idle way too slowly. Yesterday it got worse, and now will barely
idle.
If I do not constantly work the gas pedal, it will stall (in or out
of
gear). Now I am getting a check engine light, which goes out once
the
speed gets up high enough for it to keep running. Once you are
moving,
it runs fine.

I checked the really simple stuff, air filters, plugs, cap, rotor,
ignition wires, no wires knocked off of sensors, etc. None of that
changed anything. This has the "feel" (whatever that means) of a
fuel
delivery problem, but I have no solid reason for saying that. I am
an
OK backyard mechanic, but a slightly stupid as to how to diagnose
EFI
type problems, or maybe even how to narrow it down.

Any thoughts on anything else to try before I (GASP!) relent and
drop
it with my mechanic?

I appreciate any and all suggestions.
Thanks very much,
AL A.

Here's a list of the codes and processor pin assignments I scanned
form a slide card....


http://home.tir.com/~artemus/Impeller/Scan10113.JPG

"Rick" wrote in message
ink.net...
Here's a list of the codes and processor pin assignments I scanned
form a slide card....


http://home.tir.com/~artemus/Impeller/Scan10113.JPG


If your strategy is different, post it and I'll rescan
appropriately...

On Tue, 08 Nov 2005 16:42:13 -0500, with neither quill nor qualm, Al
A. quickly quoth:

Hi all,
Sort of OT, but my truck, being a 1990 is still made of metal. And
lacking a NG called rec.crafts.metalNOTworking, I thought I might try
here. I also posted to alt.autos.for.pickups, but I almost always get
most excellent advice from RCM.

Anyhow...

I have a 1990 F150 XLT, 2WD, auto trans, 5.0L EFI, A/C, dual fuel
tanks. About 90K miles on the (2nd) engine. In the last week or so, I

Mine's a '90 with 107k on the original engine.


have had a really intermittent problem. When driving at a steady speed
maybe 40-50 mph, the engine would "stumble" almost like it was cutting
out for just a second. It would do this 2 or 3 times, then run fine.
Otherwise, it ran smooth as can be. No "check engine" light. A couple
of days ago, this seemed to progress to happening more often and also
sometimes running very rough at idle, almost like it was trying to
idle way too slowly. Yesterday it got worse, and now will barely idle.
If I do not constantly work the gas pedal, it will stall (in or out of
gear). Now I am getting a check engine light, which goes out once the
speed gets up high enough for it to keep running. Once you are moving,
it runs fine.

I'd give odds that you have the same thing I just repaired. Mine quit
idling in town and I had to give it a bit of gas the 2 days before I
had it properly checked it out. I called Ford and they told me the
throttle body came with a new TPS and was only $237 plus installation.
(~$400 dealer job for an hour's work, FEH!)

I called the junk yard and they had one for $50 which took me about
half an hour to install.I had a dual problem. Mine sprung a leak in
the heater hose bypass tube. Of course, they're factory installed and
no press-in tube is available.


I checked the really simple stuff, air filters, plugs, cap, rotor,
ignition wires, no wires knocked off of sensors, etc. None of that
changed anything. This has the "feel" (whatever that means) of a fuel
delivery problem, but I have no solid reason for saying that. I am an
OK backyard mechanic, but a slightly stupid as to how to diagnose EFI
type problems, or maybe even how to narrow it down.

Any thoughts on anything else to try before I (GASP!) relent and drop
it with my mechanic?

I took mine by the local electronic diagnostic shop (freebie checkup
with a local Entertainment book coupon) and they confirmed that it was
either the throttle positioning switch (which I suspected) or the
throttle position solenoid. Both came with the used throttle body.


I appreciate any and all suggestions.

Between the intake manifold (that big aluminum casting on the
passenger side of the truck) and the plastic/rubber air intake
tubing is the dual-throated throttle body. It is bolted on with 4
bolts and the throttle cable clips onto the top of it. My gasket came
off in one piece so I salvaged that, too. The other connections were
the 2 heater hose bypasses and the intake tubes, 4 wire clamps.
See if you can find a nice one at a wrecking yard. Mine was guaranteed
to work so there was no big deal there.

The throttle body consisted of 2 types of metal, aluminum housing and
steel throttle and hose piping, so we're entirely on topic here.

G'luck!


================================================== ========
CAUTION: Do not use remaining fingers as pushsticks!
================================================== ========
http://www.diversify.com Comprehensive Website Development

Autozone has a website with much info for testing and diagnostics. You have
to log in and select a vehicle then go to the Repair info section and look
at the repair guide.
http://www.autozone.com/servlet/UiBr...3d800a2dc3.jsp
The link may not work as it is under my log in but that is the link to Using
a voltmeter to read the diagnostic codes on a EECIV system...You may have
the EECV though?
To add my WAG to the bunch ... I would look at the TFI ignition module on
the side off the dizzy. Probably should have a spare handy if it isn't the
problem as it will be soon
"Al A." wrote in message
...
Thanks for all of the replies, guys! I've got my work cut out for
tomorrow afternoon, I guess. That is exactly what I was hoping for.

I did try an autozone to get the code read, but the one I was at only
had a reader for OBD2 systems, mine is too old for OBD2. Said that
they probably lost it!

I think I may have the dreaded fuel-filter-in-the tank, as i looked
but could not find an external one, but I am planning to look again
and ask my parts guy to check if he lists one. I have the same problem
running on either of my tanks, which as it happens, each have fuel
from a different gas station. So I am thinking bad fuel/water is
unlikely.

Checked for the loose distributor and the cracked air duct from the
air cleaner box (wasted 4 days on THAT problem a few years back with
another car. good call Jim!) This has the dual heavy rubber air hoses
that look like oversized radiator hose, rather than the corrigated
plastic duct.

I have to take a look at a manual to see how to get the code to read
out. There is another place around here that may do a freebie or
minimal cost code scan that is more likely to have a scanner that old.

Also have to take a closer look through all of the vacuum lines, etc.

And please Dan, don't get the whole Chevy/Ford war started here,
PLEASE!!

Thanks again for all of the info.

-AL A.

Al A. wrote:
Hi all,
Sort of OT, but my truck, being a 1990 is still made of metal. And
lacking a NG called rec.crafts.metalNOTworking, I thought I might try
here. I also posted to alt.autos.for.pickups, but I almost always get
most excellent advice from RCM.

Anyhow...

I have a 1990 F150 XLT, 2WD, auto trans, 5.0L EFI, A/C, dual fuel
tanks. About 90K miles on the (2nd) engine. In the last week or so, I
have had a really intermittent problem. When driving at a steady speed
maybe 40-50 mph, the engine would "stumble" almost like it was cutting
out for just a second. It would do this 2 or 3 times, then run fine.
Otherwise, it ran smooth as can be. No "check engine" light. A couple
of days ago, this seemed to progress to happening more often and also
sometimes running very rough at idle, almost like it was trying to
idle way too slowly. Yesterday it got worse, and now will barely idle.
If I do not constantly work the gas pedal, it will stall (in or out of
gear). Now I am getting a check engine light, which goes out once the
speed gets up high enough for it to keep running. Once you are moving,
it runs fine.

I checked the really simple stuff, air filters, plugs, cap, rotor,
ignition wires, no wires knocked off of sensors, etc. None of that
changed anything. This has the "feel" (whatever that means) of a fuel
delivery problem, but I have no solid reason for saying that. I am an
OK backyard mechanic, but a slightly stupid as to how to diagnose EFI
type problems, or maybe even how to narrow it down.

Any thoughts on anything else to try before I (GASP!) relent and drop
it with my mechanic?
Yes. You probably haven't changed the PCV filter, and oil muck has been
sucked into the idle air control valve. (This doesn't perfecly fit
with the stumble at constant speed, but there may be more than one
problem. That one could be a dirty plug or leaky spark cable).
We had a 1993 Taurus, I think, that had this slow idle problem.
The Ford procedure is to replace the idle air valve-motor assembly
at about $150. I'd take a crack at cleaning it. You might be able to
get the engine vacuum to suck some solvent through it. Also, you
would want to start it up, and then let it idle gradually slower until
it stalls, so the computer would have made the valve go to the full-open
position. (I'm sure Ford had made sure you can't open the valve for
cleaning.)

Jon

Peter Grey wrote:
There are a lot of things that could cause your problem. The first thing I
would do is go to your local parts store and get a code reader. They're
cheap (the last one I bought was like $19) and it'll translate the code(s)
that are causing the check engine light to go on. Most code readers come
with a book that'll tell you what the codes mean.

Actually, I think you can read the code by jumpering two terminals on
the diagnostic plug under the hood. Then you turn the key to on, and
it will blink the codes on the check engine light.

They may also have a diagnostic procedure that can be triggered by
a sequence of manipulating the key and the gas pedal. Something like
turn key on, press gas pedal to floor, turn key off, release gas pedal
and turn key to start. It runs a 2-minute test sequence that ramps
engine speed up and down, disables one bank at a time to check the
oxygen sensors and a bunch of other stuff. When done, it will report
a different set of codes.

I got the Audel's book, but their interpretation of the codes was all
wrong! It called out stuff that was totally unrelated to the problem,
so I ended up having the dealer fix it for an outrageous cost.
So, you might check around to see if somebody has a list of fault codes
that is known to work for this engine any year.

Jon

Al A. wrote:
I think I may have the dreaded fuel-filter-in-the tank, as i looked
but could not find an external one, but I am planning to look again
and ask my parts guy to check if he lists one. I have the same problem
running on either of my tanks, which as it happens, each have fuel
from a different gas station. So I am thinking bad fuel/water is
unlikely.

No, it isn't the fuel filter. That could DEFINITELY cause problems
when cruising, even worse when accelerating, but is not likely
to cause a slow idle.

Jon

On Tue, 08 Nov 2005 22:48:22 -0500, with neither quill nor qualm, Al
A. quickly quoth:

Thanks for all of the replies, guys! I've got my work cut out for
tomorrow afternoon, I guess. That is exactly what I was hoping for.

I did try an autozone to get the code read, but the one I was at only
had a reader for OBD2 systems, mine is too old for OBD2. Said that
they probably lost it!

I think I may have the dreaded fuel-filter-in-the tank, as i looked
but could not find an external one, but I am planning to look again
and ask my parts guy to check if he lists one. I have the same problem
running on either of my tanks, which as it happens, each have fuel
from a different gas station. So I am thinking bad fuel/water is
unlikely.

I thought it might be a fuel filter problem, too, but when I switched
tanks, the problem went with it. The repair place I went to did a fuel
flow test, too, so that was covered.

Like I said, good odds it's your TPS. Your problem was identical to
mine (and I'm a retired mechanic.)


I have to take a look at a manual to see how to get the code to read
out. There is another place around here that may do a freebie or
minimal cost code scan that is more likely to have a scanner that old.

Yeah, that's what I did. It beats Ford dealership's $78 diagnostic
fee all to hell.


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when an attractive woman enters the room. || Full Website Programming

In article , Al A. says...

I think I may have the dreaded fuel-filter-in-the tank, as i looked
but could not find an external one, but I am planning to look again
and ask my parts guy to check if he lists one. I have the same problem
running on either of my tanks, which as it happens, each have fuel
from a different gas station. So I am thinking bad fuel/water is
unlikely.

Fuel pump/line/filters/tank vent issues can be resolved
exactly by putting a pressure gage at the inlet of the
injector rail. Zip tie the gage to the *outside* of the car,
I used the side view mirror on my toy camry.

I silver soldered a fitting to a spare banjo bolt to tap in
and measure that pressure while the car was running. Another
issue for your EFI system is, there's an injector rail bypass
pressure regulator. The rail pressure is designed to track
the intake manifold pressure, they do this by porting manifold
vacuum to a bypass regulator valve at the end of the rail that
bleeds pressure back to the fuel tank via a return line.

If that regulator is defective strange things can happen.

Checked for the loose distributor and the cracked air duct from the
air cleaner box (wasted 4 days on THAT problem a few years back with
another car. good call Jim!) This has the dual heavy rubber air hoses
that look like oversized radiator hose, rather than the corrigated
plastic duct.

OBD One won't tell you too much. It won't for example, tell you
if that intake snorkel was leaking. It won't tell you that the
injector screens inside the rail are loading up and clogging, both
of which were happening to that camry. It never threw any error
code at all. Basically OBD one just tells you 'you need to change
the oxygen sensor.' There can be a lot of fuel problems that never
cause codes.

Jim


--
==================================================
please reply to:
JRR(zero) at pkmfgvm4 (dot) vnet (dot) ibm (dot) com
==================================================

On Tue, 08 Nov 2005 16:42:13 -0500, Al A.
wrote:

Hi all,
Sort of OT, but my truck, being a 1990 is still made of metal. And
lacking a NG called rec.crafts.metalNOTworking, I thought I might try
here. I also posted to alt.autos.for.pickups, but I almost always get
most excellent advice from RCM.

Anyhow...

I have a 1990 F150 XLT, 2WD, auto trans, 5.0L EFI, A/C, dual fuel
tanks. About 90K miles on the (2nd) engine. In the last week or so, I
have had a really intermittent problem. When driving at a steady speed
maybe 40-50 mph, the engine would "stumble" almost like it was cutting
out for just a second. It would do this 2 or 3 times, then run fine.
Otherwise, it ran smooth as can be. No "check engine" light. A couple
of days ago, this seemed to progress to happening more often and also
sometimes running very rough at idle, almost like it was trying to
idle way too slowly. Yesterday it got worse, and now will barely idle.
If I do not constantly work the gas pedal, it will stall (in or out of
gear). Now I am getting a check engine light, which goes out once the
speed gets up high enough for it to keep running. Once you are moving,
it runs fine.

I checked the really simple stuff, air filters, plugs, cap, rotor,
ignition wires, no wires knocked off of sensors, etc. None of that
changed anything. This has the "feel" (whatever that means) of a fuel
delivery problem, but I have no solid reason for saying that. I am an
OK backyard mechanic, but a slightly stupid as to how to diagnose EFI
type problems, or maybe even how to narrow it down.

Any thoughts on anything else to try before I (GASP!) relent and drop
it with my mechanic?

I appreciate any and all suggestions.
Thanks very much,
AL A.

You replaced the fuel filter when again?

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

On Tue, 08 Nov 2005 22:48:22 -0500, Al A.
wrote:

Thanks for all of the replies, guys! I've got my work cut out for
tomorrow afternoon, I guess. That is exactly what I was hoping for.

I did try an autozone to get the code read, but the one I was at only
had a reader for OBD2 systems, mine is too old for OBD2. Said that
they probably lost it!

I think I may have the dreaded fuel-filter-in-the tank, as i looked
but could not find an external one, but I am planning to look again
and ask my parts guy to check if he lists one. I have the same problem
running on either of my tanks, which as it happens, each have fuel
from a different gas station. So I am thinking bad fuel/water is
unlikely.

Checked for the loose distributor and the cracked air duct from the
air cleaner box (wasted 4 days on THAT problem a few years back with
another car. good call Jim!) This has the dual heavy rubber air hoses
that look like oversized radiator hose, rather than the corrigated
plastic duct.

I have to take a look at a manual to see how to get the code to read
out. There is another place around here that may do a freebie or
minimal cost code scan that is more likely to have a scanner that old.

Also have to take a closer look through all of the vacuum lines, etc.

And please Dan, don't get the whole Chevy/Ford war started here,
PLEASE!!

Thanks again for all of the info.

-AL A.

Im sure you know how to check for air leaks using the Carby Cleaner or
WD-40 method? Spray things an area at a time and listen for engine
RPM changes?

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

On Tue, 08 Nov 2005 21:11:09 -0800, Larry Jaques
wrote:


I have a 1990 F150 XLT, 2WD, auto trans, 5.0L EFI, A/C, dual fuel
tanks. About 90K miles on the (2nd) engine. In the last week or so, I

Mine's a '90 with 107k on the original engine.


Geeze..you keep it parked in the garage?

Gunner, 94 Mazda/Ranger, 3.0, 380,000 miles

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

On Tue, 08 Nov 2005 23:52:22 -0600, Jon Elson
wrote:


Any thoughts on anything else to try before I (GASP!) relent and drop
it with my mechanic?
Yes. You probably haven't changed the PCV filter, and oil muck has been
sucked into the idle air control valve. (This doesn't perfecly fit
with the stumble at constant speed, but there may be more than one
problem. That one could be a dirty plug or leaky spark cable).
We had a 1993 Taurus, I think, that had this slow idle problem.
The Ford procedure is to replace the idle air valve-motor assembly
at about $150. I'd take a crack at cleaning it. You might be able to
get the engine vacuum to suck some solvent through it. Also, you
would want to start it up, and then let it idle gradually slower until
it stalls, so the computer would have made the valve go to the full-open
position. (I'm sure Ford had made sure you can't open the valve for
cleaning.)

Jon

Just a heads up..the Taurus 3.0 is the same basic engine as the Ranger
3.0..and the idle motor will interchange, but the connector on one is
straight, the other is at a 90 degree. And there are more Taurus in
the wrecking yard than than Rangers. So you can get one for about $5
off a Taurus (for Ranger/Taurus owners)

Same with throttle position sensors G

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

On Wed, 09 Nov 2005 17:10:15 GMT, with neither quill nor qualm, Gunner
quickly quoth:

On Tue, 08 Nov 2005 21:11:09 -0800, Larry Jaques
wrote:


I have a 1990 F150 XLT, 2WD, auto trans, 5.0L EFI, A/C, dual fuel
tanks. About 90K miles on the (2nd) engine. In the last week or so, I

Mine's a '90 with 107k on the original engine.

Geeze..you keep it parked in the garage?

No, I've been home-based and self-employed since just after buying it.
I don't need to travel much so my 700 mile trip to CA annually is the
longest exercise it gets. Town is 15mi RT at most, and Medford is 50mi
RT.


Gunner, 94 Mazda/Ranger, 3.0, 380,000 miles

Man, you LoCal dudes rack up the mileage. g
And in the middle of the HelL.A. traffic pattern, too.
Sincere condolences, Gunner. (BTDT and it sucks. Luckily,
Terry always drove us in his van or Caddie when we had a
machine to fix in HelL.A.)


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when an attractive woman enters the room. || Full Website Programming

You guys are awesome. I got exactly 2 replies on the ford truck NG.
30+ here. Oh well.

Found the fuel filter and changed it. Didn't help. It was old anyhow
so no problem. To quote a famous (RCM) American, shrug

Followed the instructions on the autozone link that Glenn posted. Got
3 codes that, according to the card Rick scanned (Thanks Rick!!) tell
me the following (in order):

53 Throttle position sensor above max voltage
63 Throttle position sensor below min voltage
31 EGR valve position sensor or EGR vacuum regulator below min
voltage

Those results agree with the autozone page, so you got the right
setup, Rick.

Just a bout the time I got that much info, it got real dark and
started raining on me. yuck. So I came in to look up the codes.
If it lets up, I may just go back out with the Big Lights and follow
those up. Likely will check out that idle air valve, too, as it looks
fairly easy to get at. The autozone page gives some quickie
voltmeter/ohmmeter type tests for those devices, so I can try to see
if I can verify any of these. Looks like I may end up doing as Larry
did and hitting the boneyard tomorrow.

Like I said, you guys are awesome. I'll let you know what I find out.

Appreciate all of the help!

-AL A.

"Al A." wrote in message
...

You guys are awesome. I got exactly 2 replies on the ford truck NG.
30+ here. Oh well.

Found the fuel filter and changed it. Didn't help. It was old anyhow
so no problem. To quote a famous (RCM) American, shrug

Followed the instructions on the autozone link that Glenn posted. Got
3 codes that, according to the card Rick scanned (Thanks Rick!!) tell
me the following (in order):

53 Throttle position sensor above max voltage
63 Throttle position sensor below min voltage
31 EGR valve position sensor or EGR vacuum regulator below min
voltage

Those results agree with the autozone page, so you got the right
setup, Rick.

Just a bout the time I got that much info, it got real dark and
started raining on me. yuck. So I came in to look up the codes.
If it lets up, I may just go back out with the Big Lights and follow
those up. Likely will check out that idle air valve, too, as it looks
fairly easy to get at. The autozone page gives some quickie
voltmeter/ohmmeter type tests for those devices, so I can try to see
if I can verify any of these. Looks like I may end up doing as Larry
did and hitting the boneyard tomorrow.

Like I said, you guys are awesome. I'll let you know what I find out.

Appreciate all of the help!

-AL A.



Good luck with it! You can get the OBD-I tester at Wal-Mart for about $25.
If you don't mind, please stop bragging about getting two responses in a
Ford truck forum. :-) For those who don't know, the Ford truck forums are
a great place to brag about what kind of motor and exhaust system one has,
but not so good if you really need help. He was lucky to get more than one
response, unfortuantely.

On Wed, 09 Nov 2005 16:54:38 -0500, with neither quill nor qualm, Al
A. quickly quoth:


You guys are awesome. I got exactly 2 replies on the ford truck NG.
30+ here. Oh well.

Found the fuel filter and changed it. Didn't help. It was old anyhow
so no problem. To quote a famous (RCM) American, shrug

I think you meant "infamous", didn't you, Al? wink


Followed the instructions on the autozone link that Glenn posted. Got
3 codes that, according to the card Rick scanned (Thanks Rick!!) tell
me the following (in order):

53 Throttle position sensor above max voltage
63 Throttle position sensor below min voltage
31 EGR valve position sensor or EGR vacuum regulator below min
voltage

I believe mine were 23 and 63.


Those results agree with the autozone page, so you got the right
setup, Rick.

Just a bout the time I got that much info, it got real dark and
started raining on me. yuck. So I came in to look up the codes.
If it lets up, I may just go back out with the Big Lights and follow
those up. Likely will check out that idle air valve, too, as it looks
fairly easy to get at. The autozone page gives some quickie
voltmeter/ohmmeter type tests for those devices, so I can try to see
if I can verify any of these. Looks like I may end up doing as Larry
did and hitting the boneyard tomorrow.

Oh, goodie! I get to do an ITYS!


Like I said, you guys are awesome. I'll let you know what I find out.

Appreciate all of the help!

Jewelcome. That'll be $37.50, please. snicker


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when an attractive woman enters the room. || Full Website Programming

On Tue, 08 Nov 2005 16:42:13 -0500, Al A.
wrote:

Hi all,
Sort of OT, but my truck, being a 1990 is still made of metal. And
lacking a NG called rec.crafts.metalNOTworking, I thought I might try
here. I also posted to alt.autos.for.pickups, but I almost always get
most excellent advice from RCM.

Anyhow...

I have a 1990 F150 XLT, 2WD, auto trans, 5.0L EFI, A/C, dual fuel
tanks. About 90K miles on the (2nd) engine. In the last week or so, I
have had a really intermittent problem. When driving at a steady speed
maybe 40-50 mph, the engine would "stumble" almost like it was cutting
out for just a second. It would do this 2 or 3 times, then run fine.
Otherwise, it ran smooth as can be. No "check engine" light. A couple
of days ago, this seemed to progress to happening more often and also
sometimes running very rough at idle, almost like it was trying to
idle way too slowly. Yesterday it got worse, and now will barely idle.
If I do not constantly work the gas pedal, it will stall (in or out of
gear). Now I am getting a check engine light, which goes out once the
speed gets up high enough for it to keep running. Once you are moving,
it runs fine.

I checked the really simple stuff, air filters, plugs, cap, rotor,
ignition wires, no wires knocked off of sensors, etc. None of that
changed anything. This has the "feel" (whatever that means) of a fuel
delivery problem, but I have no solid reason for saying that. I am an
OK backyard mechanic, but a slightly stupid as to how to diagnose EFI
type problems, or maybe even how to narrow it down.

Any thoughts on anything else to try before I (GASP!) relent and drop
it with my mechanic?

I appreciate any and all suggestions.
Thanks very much,
AL A.


Hey Al,

Different vehicle and manufacture (Chrysler mini-van), but a 1989 so
some sort of technical state-of-the-art-of-the-day. Exactly the same
symptoms, progressive worsening and all, as you describe, and it
turned out to be something called "The Crank Center", and required the
replacement of some kind of sensor. Can't recall the cost.

Take care.

Brian Lawson,
Bothwell, Ontario.