Erratic Idle AFTER Warm-Up
Thread Starter
Instructor
Joined: Sep 2000
Posts: 135
Likes: 0
From: Slidell Louisiana
Erratic Idle AFTER Warm-Up
My 94 starts fine, idles great, recently had new plugs installed, accelerates fine. After driving awhile and reaches operating temperature, the car will struggle at idle at a stop light under a load (in gear). Seems to be fine if placed in neutral but if in Drive, it will produce an erratic idle. Give it the gas, pulls away fine - no problem until next stop light. No codes registered. A search on this subject, specific to the 92 - 96 group, produced several like situations - but I never did see a follow-up post from someone who corrected the situation and how they did it. Any help here would be appreciated and archived.
Thanks, Champ
Thanks, Champ
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
Lots of things you can check. Fuel pressure, filter, bad wires and the usual tune up stuff. But you are probably going to end up at the opti. Just like mine, no codes, acting up after warm up, poor acceleration when loaded. There is a wide variation in symptoms that the opti could produce. 
Thread Starter
Instructor
Joined: Sep 2000
Posts: 135
Likes: 0
From: Slidell Louisiana
Fuel pressure seems fine - pulls hard all the though 6k. No problems accelerating any time - even when warmed up. No pops, hesitation when cruising even at low speeds. When you stop at the red light, you can feel (and see on the rpm gauge) the idle going up, then coming down a bit, going back up - shift to neutral it evens out. Hoping it is not the opti. Will continue to look at other posts for other solutions and will keep this thread posted with final comments. Thanks PCOLT
Burning Brakes
Joined: Dec 2000
Posts: 1,161
Likes: 0
From: Orangeburg, NY
It could be your IAC, with carbon build-up. In the front of the throttle body, between the two intake ports, on the bottom of the body, there is a small air intake for the IAC. Spray some air intake cleaner into the hole and let it stand for approx. 1 minute. then start the car for a minute and shut it off. Do this a couple of times and it should clear the problem. It is better when the engine is cold when doing this and be sure to use AIR INTAKE CLEANER and NOt carb cleaner.
