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[email protected] clare@snyder.on.ca is offline
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Default EPA caught VW cheating - how does the car know it's being tested?

On Sat, 19 Sep 2015 20:26:34 -0500, "." wrote:

On 9/19/2015 7:38 PM, wrote:
On Sat, 19 Sep 2015 16:28:20 -0500, "." wrote:

Fuel additives and larger injectors can defeat the effectiveness
of emission controls, not that they'll necessarily increase power.


Bigger injectors will just be dialed back by the computer as the O2
sensors report a richer than optimum mixture. Too big and the engine
will go into "limp mode" because the engine remains too rich even with
the calibration at lean limit. Power will suffer.


You questioned how one could simply defeat emission controls.
You were provided with effective examples.

Pull off any number (EGR, PCV, Sensor ...) of wires, hoses,
or lines; one could also easily have multiple devices either
fail or disabled (that don't prevent the engines from running)
and significantly decrease the efficiency, and increase the
pollution output, of the engine.

Yes, but it will turn on the CEL and in many cases prevent the engine
from starting, even if it will run after starting. ANd it will run
like crap when it runs. NO incentive to do it.


Again, you questioned how one could simply defeat emission
controls. You were provided with effective examples.

so that what left the
manufacturer and what was on the road were not necessarilly the same.

And those that in any manner overrode emission controls were
an insignificant percentage of the motoring public.

You would be surprised how many Olds 350 rockets back in the mid
seventies had the timing significantly altered to eliminate
overheating when pulling a trailer, or how many "super six" mopars had
the carburetion and timing adjusted off-spec to get rid of
"driveability problems" - and how many "lean burn" mopars were
"converted" to non-lean-burn without changing the camshaft (which was
required if you were going to be anywhere CLOSE to passing emissions)
and how many AIR systems were removed from GM engines - and how many
EGR systems were disconnected ---- just for starters. (under the
mistaken idea that they could get better mileage by simply removing
them)

I'm only surprised at the length of your run-on sentence.

I worked tune-up and electrical in '74-'76 at a Mopar dealer.
Remember the red, sometimes off white, idle mixture limiting,
plastic stops that covered the screw heads on Carter's (which
also had an issue with warping, requiring a retro-fit brace)?
Periodic rough idle complaints on new cars were sometimes
addressed by first subjecting such engines to a full Sun Scope
(on a rail) diagnostic. Were no issues found, I would remove
them, as emissions testing was neither available nor required.
Never once had a comeback or complaint.


Used to remove the limit caps, adjust to spec (or modified spec) and
then replace the caps, as required by law. We did the adjustment using
the exhaust gas analyzer that was part of the Sun, Allen, Marquette,
or Rotunda diagnostic scope I was using at the time. Quite a few were
off spec from the factory.


"Periodic rough idle complaints on new cars ..." I knew I heard
that somewhere. After verifying everything else was within
spec, and given that emission testing was not mandatory, the
scope, a vacuum gauge, and a tach was all that was really
necessary for an experienced mechanic to adjust the idle
mixture.

AMC,Chrysler, Mazda and Toyota
dealershipsduring that time period, as well as independent repair
shops

The numbers WERE significant.\

No they were not. "Cleaner air" evolved from unleaded fuel,
catalytic converters, fuel injection, and overall drive train
computer management of hundreds of millions, not the
hobbyists' thousands, of vehicles on US roads.


It wasn't hobbyists - it was "hack mechanics" who didn't know
anything about emmission controls and defeated them in an attempt to
"solve" problems. - some real and some immagined.


Laughable ignorance. No, what led to cleaner air was unleaded
fuel, catalytic converters, multiport fuel injection and overall
drive train computer management (MAF, MAP, IAT ... sensors,
among others) of HUNDREDS of millions of cars replacing
the archaic Kettering ignition, centrifugal spark advance,
coil choke-manifold vacuum-non linear venturi based
carbureted engines. Sad that you don't seem to know and
understand something that fundamental.

Exactly what are you trying to say??? My reply was to say there were
many instances of people - hobbyists and mechanics alike, screwing
with emmission controls in an attempt to defeat them and get better
mileage and power, and getting (usually) neither.

Nowhere did I even suggest any of that had any positive effect on
emmission reductions. What "laighable ignorance" are you talking
about???
Of course it was " unleaded fuel, catalytic converters, multiport fuel
injection and overall drive train computer management (MAF, MAP, IAT
.... sensors, among others) of HUNDREDS of millions of cars replacing
the archaic Kettering ignition, centrifugal spark advance, coil
choke-manifold vacuum-non linear venturi based carbureted engines"
that made the difference. Where did I ever suggest otherwize??

Or are you saying the emission control inspections were not
instrumental in reducing emmissions? They WERE for a short period of
time, partly by catching the vehicles that were "screwed with" by
hobbyists and "hack mechanics" - but they have become virtually
redundant today because the sophisticated engine management systems
can pretty well tell you if the vehicle is running within design specs
with a cheap OBD2 code reader - or even your cell phone with the
proper software and OBD2 code reader adapter.

No idea who or what you are since you hide your identity.
I was a carreer proffessional mechanic for years, as well as an
automotive technology instructor at both secondary and post-secondary
(trade) level.