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Information on Idle Air Control Motor 1994 Caravan 3.3L

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Herein I provide information from my measurements and what others have said, suitably digested.​

The IACM is a simple stepper motor, one-quarter turn each step. One winding turns it one way, the other the other.​

I measured each winding at 50 ohms.​

The factory service manual states that pintle projection should be no more than 1 inch, mine was 1 1/8”. I was able to retract the pintle by wiggling while pushing, thanks to an Allpar member.​

(Chrysler assumes the mechanic has Chrysler’s special scan tool which can command things to occur. Another member suggested that just powering the ECM would retract it, I did not try that.)​

Others claimed the ECM would figure out the right pintle position somehow. While that may eventually be true, I judge it better when having start/idle problems to begin with what Chrysler specifies. (The IACM depends on the MAP sensor to know the engine is running as manifold pressure decreases. It cannot use the O2 sensor initially as it must be hot to work properly, it is electrically heated in addition to exhaust heat so will warm up quickly.)​

BTW, after you lose a screw, you may want to know that the attaching screw thread is 10-32, shank 5/8”, pan head. Screwdriver is Torx T25. If substituting with standard screw note that the Chrysler screw has locking compound on the threads so you need to use similar or a lockwasher. Yes, standard US fine thread, not metric.​

(Removing the IACM by itself is awkward by because there is limited clearance to the brake master cylinder. Fortunately I had a hex-to-¼” square drive adapter so could use a ¼” ratchet. Magnetism is desirable as holding the screw while taking it out of the area is somewhat awkward. Magnetism is desirable as holding the screw while taking it out of the area is somewhat awkward, I’m going to put a strip magnet in my special bit set and ¼” ratchet set, as some adapters are only weakly magnetized. And find my grabber tool.)​