I've been chasing a sudden 2 mpg drop, going through all the standard stuff and not getting anywhere...

Truck seems to be running fine. Only noticeable change is the idle RPM has a periodic +/-20 rpm swing, say twice a minute or more. It used to hold +/-3 RPM rock steady.

Today I noticed the A/C compressor conitually cycling without the A/C being on. Condensor pipes cold etc.. The compressor cycling coincides with the RPM swings. Sure can't recall this behavior beeing normal.

Is something up, or is my ghost hunt starting to drive me insane?

-Mike

 

Sorry, disregard. Found through other posts that A/C compressor cycling is normal for all but a couple switch settings.

The ghost hunt is getting to me......

 

Yup, the a/c compressor runs in all settings except vent and floor