On Feb 26, 12:17*pm, "Steve W." wrote:
Half-Nutz wrote:
On Feb 25, 10:17 pm, "Robert Swinney" wrote:
Thanks for the tentative conformation, Bruce. *I have no OBD code reader so I don't know if it is
throwing a code. *The check engine light does not come on. *It did come on one time after heavy
acceleration at freeway speed to get out of a jam. *It stayed on for about 20 seconds and then went
off. *It hasn't come on since, although the low idle miss has gotten a little worse.

Bob Swinney
"Bruce L. Bergman" wrote in messagenews:iv2cq49oeuhlq0tuvlvfdie6svamsdfn7c@4ax .com...
On Wed, 25 Feb 2009 20:06:07 -0600, "Robert Swinney"

wrote:
Our 2004 Pontiac Bonneville GXP has developed a low speed miss. *It is particularly noticeable when
the engine is cold. *It seems to miss only at idling speed and is worse before the engine warms up.
The miss goes away when you load the engine under acceleration. *At only 36000 miles it shouldn't
need a major tune-up. *I am guessing a dirty fuel injector. *Any ideas appreciated.
Bob Swinney
* Silly question number one: *Is it throwing a computer code and
lighting the Check Engine Light? *And if so, what are the codes?

* If it's enough to worry about, the OBD-II computer will notice it.

* Only at idle, worse when cold... *You might be right about a dirty
injector. * Try some Chevron Techron additive in the tank first.

* If that doesn't work, buy or borrow a fuel-rail connected injector
cleaning kit and a can of the cleaning solvent. *The kit costs about
what you'd pay to have it done once, and if you are careful to buy a
decent one it will be good for many years.

* *-- Bruce --

What you want to do, is read out the code.
That vintage, they have temporary codes, that they save, for a while.
You can read out the code with nothing more than a jumper wire, it
will flash the codes out on the dashboard light.

For example, code 23 is two blinks, delay, three blinks, long delay,
repeat...

A problem that it notices, then goes away, it still saves, for a
while.
If the problem is solid, the light stays on. if it gets better, it
goes out, but remembbers the code(s).
I had very good luck, it told me exactly What was wrong.. Changing
that.. Fixed it.
Neat system.

if it was a 94 he could use a jumper wire. An 04 on the other hand
cannot use a jumper to pull the codes.

--
Steve W.- Hide quoted text -

- Show quoted text -

A moot point now that's in the hands of the local reps, but most of
the local chain auto parts places will get their reader out and read
out your codes for free. Autozone definitely will do this. They
probably make a few sales of sensors that way.

Stan