'99 SL2 idle bounce, stall, and stick

Hello group,

I have a '99 SL2 5-spd. The following two issues have persisted for
some time now. I have become increasingly concerned by it, thinking it
was just mildly annoying at first. Some times it sticks at 2k+ out of
gear, and a restart is the only way to "cure" it, or it will just decide
it's done revving, and will resume normal operation. Other times, it
bounces to near zero with the a/c on, and will sometimes stall. There
does seem to be a weak link with temperature, with the high idle
problem. I understand the load on the little 4 with the a/c compressor
may cause some idle fluctuation when the clutch is suddenly disengaged,
but it's definitely abnormal in that regard.

Years and years of EFI Fords have idle air control valves that gunk and
cause problems, so that was my first thought. However, I don't know GM
products of any era well at all. Is that likely the issue here?

Thanks all

 

Idle air control solenoid/valve would be my first guess, but a person
shouldn't replace parts based on a guess. Stop by Autozone and get the
stored codes read for no charge. Then go from there.

Lane [ lane (at) evilplastic.com ]

 

I didn't know Autozone did that. Shows what I normally work on, things
tuned by hand. Thanks for your input!

--
Wound Up
ThunderSnake #65

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IMHO:

When every I have a problem with rpms high or low, I go right for
cleaning the throttle body.

If I have a low rpm, to an eventual stall, I go for the Coolant
Temperature Sensor.

After this two, if I still have problems I panic.

hth,

tom @ www.NoCostAds.com

 

Wound Up-
You know - I would think the problem would have changed in 5 or 6 years
(ie. the engine would have changed to make the same problem/symptom
unlikely).
But I've had the exact same problem with high idle.
The problem? Because of a bad coolant temp. sensor, the engine thought
the coolant was 10 below zero.
This same sensor problem occured on both my 94 and my 95 SC2 (on the
latter, it was the previous owners problem that translated into a good
deal because I knew exactly what their shade tree mechanic didnt!)
In my own case, it would idle 2000 to 2500 while the vehicle was
moving, but would drop down to 1200 or 1500 when the vehicle came to a
complete stop.
If you can, try to check the resistance of the sensor. At 80 degrees
f, it should read less than 100 ohms (I think - I dont have the manual
handy) but it Definately should not read higher than 1000.
-hope to help
DC

 

I can, I have an ohmmeter.

At 80 degrees

Many thanks! And to the others as well. I'll ceheck a few things out,
cleaning stuff is always good, and check that resistance reading....


--
Wound Up
ThunderSnake #65

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