2001 cadillac sls pulses when a/c is on


ellis479
09-28-2011, 04:09 PM
Hello,

My 2001 cadillac sls will pulse up and down @ idle when the a/c is on. It does this constantly, not like when the a/c is engaging and dissengaging. It runs smooth when a/c is off. Thanks ellis479

maxwedge
09-28-2011, 07:55 PM
The pcm is try to stabilize the idle, now as the compressor cycles the idle will vary slightly, if it is a gross change in speed, the throttle bodyand/or isc could be dirty or faulty ( the iac), a full scan may show something or an experienced tech can find out what's what.

ellis479
09-30-2011, 02:13 PM
Maxwedge,

Thanks for the information. I couldn't figure out why it only fluctuates when the a/c was running. Once again it's not like the clutch cycling, much more rapid. Thank you ellis479

ellis479
01-10-2012, 02:27 PM
Maxwedge,

I had the throttle body cleaned and the camshaft sensor replaced. This not only fixed the idle problem, but increased the gas milage dramatically. Thanks for your help...........Ellis479

maxwedge
01-10-2012, 04:07 PM
Thanks for posting back results, did a scan show a cam sensor issue?

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