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carbob81
04-30-2020, 09:06 PM
My car is very pissed at me for letting her set a long time and not getting enough time to stretch her legs.
Now she does like anything below 2000-2500 RPM.
Replaced the idle air flow valve, no happy.
Replaced the ICU, no happy. Bypassed both, different but not happy.
Smoke test for vacuum leaks, nothing found.
I can fiddle fart with the idle with the base adjustment screw on the flap inlet but that is just starving the system so get low and backfire when throttle up.
I feel I am missing something simple and basic
Removing the cold start valve for free flow and allowing open air makes the motor act very different but still not under control of the idle circuit.
No matter what is is way rich at this low RPM. The kind of rich that burns you eyes in a garage in 3-7 minutes.

I am perplexed. What to test?.
I'm missing something simple and obvious
Bob

David T
04-30-2020, 09:17 PM
Sounds like the plunger in the mixture unit is stuck.

Bitsyncmaster
05-01-2020, 05:39 AM
So are you saying your idle RPM is 2000 to 2500 or do you mean it does not run well until you get to that RPM?

dmcnc
05-01-2020, 06:12 AM
Is your throttle arm all the way down?

82DMC12
05-01-2020, 10:22 AM
Sounds like the plunger in the mixture unit is stuck.

My first thought also. You said the car was sitting for awhile. If you used ethanol gas it's total crap in like 6 to 9 months. Consider flushing the fuel system out, changing the fuel filter, and only use non-ethanol gas from now on, if you can find it. QuikTrip sells it.

My car had poor A/C a few years ago so I stopped driving it and time got away from me one summer. In less than a year my gas turned into a brown color and the engine ran like crap. Flushed everything and back to normal.