2007 Pt Cruiser

Hi! I have a 2007 Pt Cruiser Touring Edition with about 91,000 miles on it. Here’s the trouble: when idling (whether in drive or park), with the A/C on, the car will shake. But what is interesting about this shake is that it happens about every 8 seconds. The RPM’s will drop below 500, the A/C will get warmer, and the car will shake; in that order. I’m led to believe this issue obviously has something to do with A/C. I feel it’s messing with my car’s overall performance and even gas mileage if that’s possible. In addition, when I turn the A/C off I hear this weird, for lack of a better word, fart sound come from behind the center console; almost like the compressor is having trouble switching off? I’m not sure. The car overall feels sluggish and does not have the pep it used to. The oil has been changed regularly and I use good quality gasoline. What else could it be if not just the A/C? Spark plugs? Is something misfiring? Help! Thank you!!

The problem might be caused by a defective Idle Air Control valve hunting for the proper position when the AC is turned on.


The IAC valve controls the engine idle speed under all conditions.

So for example, if you were turning the steering wheel while idling, the IAC valve would raise the engine idle speed for the load the power steering pump would impose on the engine.

The same thing is suppose to happen when the AC is turned on, and the AC compressor imposes a load on the engine while idling.


Is the check engine light on . . . ?!


Thanks Tester! Never thought of that. Will definitely look into it. And no, db4690, the light is not on. Lol.

BUT! The passenger airbag light likes to come on and off as it pleases. Idk if they are connected in any way at all.

Had one that did the same thing. Never had a car cost me so much money! Could not wait to get rid of that thing. Would not own another one.

Oh good! Haha. Can’t wait to see the mechanic’s quote!