96 Deville, AC quits, idle goes crazy

Cadillac Forums | Help Us Help You | Advertise | Cadillac Parts | Cadillac News | Cadillac Classifieds

Cadillac Technical Archive | Cadillac Dealers | Cadillac Reviews | Cadillac Dealer Reviews | Cadillac Vendors

CadillacForums.com is the premier Cadillac Forum on the internet. Registered Users do not see the above ads.
+ Reply to Thread
Results 1 to 2 of 2
Cadillac DeVille 1985 to 2005 including:
1985-1992 Fleetwood, 1993 Sixty Special, All FWD Forum Discussion, 96 Deville, AC quits, idle goes crazy in Past Cadillac Vehicle Discussion; On occasion the ac stops cooloing (no compressor operation) no codes what so ever. At the same time the idle ...
  1. #1
    dlwoodtx is offline Cadillac Owners Member
    Automobile(s): 62 conv, 95 Deville
    Join Date
    Feb 2009

    96 Deville, AC quits, idle goes crazy

    On occasion the ac stops cooloing (no compressor operation) no codes what so ever. At the same time the idle goes way up, engine races to max RPMs if allowed. Again no codes. Pull over, leave in gear (to keep RPMs down) and restart and everything is fine. Got me stumped for sure.
    Idle controlled by ISC via PCM motor or not controlled by vacumm leak. AC controlled by AC controller via PCM. Beside the PCM is the any other things in common? Maybe joint wiring harness issues? Grounds. Any other ideas or known issues?

  2. Remove Advertisements

  3. #2
    Dave S Texas's Avatar
    Dave S Texas is offline Cadillac Owners Enthusiast
    Automobile(s): '87 Coupe DeVille 4.1L FWD(New engine '08) 1981 F100 '03FXDL
    Join Date
    May 2008
    Austin(area), Tx

    Re: 96 Deville, AC quits, idle goes crazy

    Many bad things happening yet no codes?! I'd first suspect a faulty controller. You can try disconnecting the battery. This will erase the RAM and control will revert to the default program. If the bad behaviour returns I'd look at replacing the controller. Maybe someone has a different idea though.....

  4. Remove Advertisements
    Cadillac Forums

+ Reply to Thread

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

What Cadillac(s) do you own? (Or type NONE)

Please select your insurance company (Optional)

Your date of birth and age are displayed in several places on the forum. Only the administrator will have access to your date of birth should you choose to hide it via the privacy option below.


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Cadillac Posting Rules

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts