Motor Vehicle Maintenance & Repair Stack Exchange is a question and answer site for mechanics and DIY enthusiast owners of cars, trucks, and motorcycles. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

When the car is idling and the A/C is turned the engine will shutter hard and/or turn off. I've already replaced the IAC valve; it was working for a little, but now it's back to shutting off.

The only other things I can think of is the electronics controlling the IAC. Any ideas?

2004 dodge neon r/t SOHC

share|improve this question
Does the ECU raise the idle when you turn on the A/C? – Timo Geusch Aug 30 '11 at 14:36
stays around 900 rpm – DustinDavis Aug 30 '11 at 16:13
I'd research if it's supposed to raise the idle - most cars I'm aware of do as the a/c compressor can add a lot of drag on the engine. – Timo Geusch Aug 30 '11 at 18:42
when the a/c turns on the IAC will open to keep the car at 900rpm. If the IAC didn't open the car would drop to 500rpm and die. – DustinDavis Aug 30 '11 at 19:02
up vote 3 down vote accepted

I would check belt tension and rotation of the pulley on the compressor.

The compressor may be exerting more drag then it is supposed to causing a further drop in RPMS then the IAC is compensating for and so causing it to stall.

It may be the pulley itself seizing which you may be able to recover with some corrosion cleaner, lubricant etc. Otherwise it may be internal of the compressor.

Also, there is supposed to be a certain amount of oil in the refrigerant to lubricate the system, perhaps you have a leak that has caused loss of this lubricant and again the compressor is taking more effort to rotate.

share|improve this answer
all good posibilities. I'll check them out. – DustinDavis Sep 1 '11 at 3:08
Ended up just buying an SRT-4. No more shuttering :) – DustinDavis Sep 20 '11 at 3:37
Heh, expensive repair, enjoy the new ride. – ManiacZX Sep 20 '11 at 18:02

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.