Idle Woes & AC Compressor Cycling

[gearz]

My '98 XLT has an interesting new problem. While idling the AC compressor will cycle on and off approximately every 10 seconds with a resultant increase of about 500 rpm each time the compressor clicks on. This happens regardless of where I have the heat/defrost/ac selector switch. The only time it doesn't happen is when the selector switch is in the off position. It can't be good for my automatic transmission to be subjected to the rpm surge while stopped in traffic. I don't need the AC here in Seattle, particularly this time of year. No check engine light.

Any ideas on what the problem may be? Can I just disconnect the lead to the compressor?

 

[Turdle]

This should help
http://www.explorerforum.com/forums/showthread.php?t=84220&highlight=IAC+valve

The IAC is also used to raise idle speed when ac cycles on--

 

[budwich]

your a/c is low on charge. Its somewhat normal for increase in idle when the ac compressor is on (engine load increases). as for when it comes on, in fords, only positions on the selector where there is "one air event" (ie. just "pointing" at your feet, or just pointing at your upper vents) DON'T cause the A/C to kick in.... check your manual.