Idle jumps to 1500rpm when a/c cycles on

[V8Notch]

My idle jumps to 1500rpm when the a/c cycles on and off. Not when the A/C is running just the pump clycling on and off.

The IAC valve is new and it idles fine other than that.

I've reset the computer by leaving the battery disconnected for a while. Sounds like I'm reving it.

 

[Big Jim M]

Sounds to me like the engine is having a hard time idleing and when the a/c load hits it the computer thinks it is dieing...so it revs the engine to keep it running.
How is the tune? How many rpm is it ideling at without the a/c working?
Big Jim

 

[V8Notch]

New plugs, fuel filter last summer, maybe 7K on them.

Idles at about 7-800rpm with out the a/c. Completely stock.

 

[naford]

Thats sounds normal. When the a/c compressor comes on the rpms increase so the motor isn't loaded. You also need to be aware that the a/c is running under defrost and other heater settings.