1985 Chrysler Le Baron Won't Pass Emissions Test

I'd be suspecting a vacuum leak. That's all the AIS motor is. It's a controlled vacuum leak; a passage around the throttle blade.

Remove the unit and look at the pintle valve on the end. I'm trying to visualize it, but all I can see is the newer style from the 1990s, which I thought was the same for '85. Try pulling the valve out by hand. It will move hard, but it should move. Years ago, with dirtier gas, it was real common for the passage to become blocked with carbon deposits from vaporized gas, resulting in an idle speed that was much too low, but that was more of a 3.0L V-6 thing.

4 cylinder carbureted cars had a problem with the fiber spacer under the carburetor shrinking causing a vacuum leak and very high idle. You might look for the same type of spacer under your throttle body. Also look for cracked and deteriorated vacuum hoses. When the engine is running, but still cold, use a spray bottle to spray water around the intake gaskets and vacuum hoses. If the idle speed drops, look in that area for the vacuum leak.

Caradiodoc