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The air conditioning unit on my 2005 Cavalier only engages when the engine is idling above a certain level (observationally, it appears to be between 1000 and 1200 rpm).

During the summer months, then, I would like to adjust the idle rpm of the engine so that the AC runs even when sitting still.

How would I do that?

Other car specs (if needed):

  • 4 cylinder
  • automatic
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up vote 1 down vote accepted

I suspect something is wrong with your AC system if the compressor is not running at idle, assuming you're idling at the correct RPM. Maybe a bad RPM sensor on the compressor?

Changing your engine idle is going to require editing your PCM. If you're not idling in the correct range, check your IAC.

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fwiw - I had an Escort station wagon years back that did the same thing .. and it was "by design" – warren Apr 12 '12 at 13:24
@warren Weird. Well, as I said, assuming your engine is actually idling where the powertrain controller wants it to be, you'll probably have to edit the code the PCM is running. Being able to flash your PCM is going to require specialized cabling and software tools. I don't know of an off the shelf tool for your application. There is enough info out there to build your own, but it would be one heck of a project. – Mark Johnson Apr 16 '12 at 17:49

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