Wondering where it is, what is its purpose. I have a rough idle and would like to explore every scenario.

Another question...random but I didn't see the need to open another thread. Maybe someone here will know. My trim around the windshield has popped loose in one corner. The clips seem to be trash, I have tried super glue, liquid nails, and some epoxy. Now, I am wondering which of the two to choose. Urethane glue or weatherstripping cement from permatex. Any experiences with either?

Sticking to one thread here...to maximize web space. Well, the cylinder on the intake you describe as the Idle Air Motor, happens to be what Bosch calls an Auxiliary Air Valve. Whatever you want to call it, I'm beginning to think it's not the problem. Thanks, for all your thoughts. It's just weird, after having the mixture adjusted, that she'll idle fine in park but will "putt" in gear. Almost to the point of stalling. I thought it might be missing but I checked my distributer cap, played with the spark wires(made sure they are making good contact and tried to get them to snap on like they used to). Maybe I need new wires but the mechanic said they checked out fine. I'm going to bring it back to the mechanic and tell him what his work is worth as of now.

If it idles fine, then it's probably not the IAC (yours should have a straight-through design and be mounted on top of the intake manifold, as opposed to underneath in the 700 series). If it hesitates under load, it could be a fuel supply problem, instead. How's your intank pump working?


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'81 GLT 245 @ 259K; '83 DL 175K

The Idle Air Control (motor) valve and Auxillary air valve are two different things. The IAC valve is part of a constant idle control circuit which your car, an '81 doesn't have. The IAC valve is a motorized cylindrical valve is unlike the Auxillary Air Valve which is on your car is a bi-metallic strip which activates a damper valve to give fast idle when cold, for only the first 10-15 seconds after the car is started, given a signal by the thermal time switch. The AAV is located on top of the valve cover usually bolted down to one of the nuts on the cover towards the center. When the temp outside is about 60 degF, the valve opening should be ~1/8 inch. If it's opened a lot more than that, (broken) and not closed when running a hot engine, OR is shut when it should be opened, an improper adjustmant of the idle screw may have beem made, which could cause poor idling conditions. Note that when the engine shakes upon startup the vibrations are intended to help this valve close properly, so it should be bolted down well. If you remove it an knock it around and it doesn't move, it is probably bad.
Now that we know you have K-Jet w/o the constant idle circuit it opens up into many other possibilities. Vacuum leaks are a big problem on K-jet as is the fuel delivery. Start to look at these things and then see.
The portion of the throttle body where the idle adjustment knob is located can get gummed up and should be cleaned periodically. Also check to see that the solenoid for the fast idle for the A/C isn't sticking, also in the block with the idle adjustment screw.
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'89 245 sportwagon, destroyed by hit & run driver, RIP. '04 V70 2.5 T Sportwagon, 12k mi and '91 245 5-speed, 209k mi, replaced the '89

The IAC valve is part of a constant idle control circuit which your car, an '81 doesn't have.

I beg to differ: it may or may not, depending on the model and location where it was originally sold. My '81 does, indeed, have an IAC ... others may or may not have the auxiliary air valve (mine does not).
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'81 GLT 245 @ 259K; '83 DL 175K

Ok, I have no IAC. That is what I have come to figure. However, question for vvpete, I just installed a new AAV from Bosch. When I put it on, it was about 37 degrees. So, being 37 outside, the hole showed a little more than an 1/8in. Does that seem right? Also, I have no A/C anymore, I pulled everything I could think of last year. You were mentioning to check the solenoid for the high idle with the A/C. Not having and A/C...is that going to affect anything or how can I check that solenoid now?

What year is your 240?
It's normally located under the intake manifold on post '85 models.
First I would remove the throttle body and clean it. Pay attention to the small holes. Use a toothbrush and some carb cleaner. Next remove the IAC valve and see if it's gummed up, clean with Q-tips carefully, and use a mix of WD-40 and carb cleaner, gently on the rotating cylinder valve, don't flood it.
Check all your hoses connected to the intake manifold, throttle body and IAC valve for leaks, also the flame trap clean/replace. This kind of service usually fixes most idle problems.
Good luck
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'89 245 sportwagon, destroyed by hit & run driver, RIP. '04 V70 2.5 T Sportwagon, 12k mi and '91 245 5-speed, 209k mi, replaced the '89

Ok, it's an 81 245. Alright, Idle Air Control valve, would be where? Do you mean auxiliary air valve? The throttle body would be where? Does anyone know of a better book than chiltons, haynes? for an 81 240?

That's the cylinder on top of the intake, what you were referring to as the AAV in the other post. The auxiliary air valve is a different beast, and may or may not be found on your model.

The Bentley manual is quite good for this model as the turbo models it covers are basically the same as far as the fuel system goes (K-jet). Also, it would be better if you stick with one thread describing your problem, rather than starting several new ones. Just a thought ...

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'81 GLT 245 @ 259K; '83 DL 175K