chirping noise driving me crazy!!
 

I have a 2001 boxster s that has an annoying chirping noise which seems to be coming from the rear passenger side. It started with one or two chirps upon start up and then would go away. Then it progressed to a few chirps usually 0-25mph. Now it chirps even at idle and speeds up as speed increases. I considered AOS but i replaced it maybe 6 months ago and i looked around everything seems fine, also loosened oil cap to see if chirp would stop and it didn't. one thing i did discover is when a/c is turned on chirp is constant, then you turn a/c off it goes back to a slow chirp. does that mean bad a/c compressor? cold air is still coming out though. also replaced belt and water pump by porsche dealer maybe 5 months ago. Anyone with some suggestions would be greatly appreciated. i need to get rid of this bird!!

eldridge58,

It sounds as if it may be coming from your accessory drive area. You may be able to pinpoint the source if you remove the access panel and have a listen. You also can remove the belt and check out the pulleys and tensioner. Then you can start the engine briefly with the belt off and see if the sound is still present.

I had a clicking noise about a year and half ago that turned out to be my alternator pulley. It sounded like an air conditioning compressor that was cycling on and off frequently due to low coolant. If your car is a manual it has the same clutched alternator pulley.

Best of luck,

ddb

A few other "chirp" sources I have seen over the years:
Loose spark plug- cheap and easy fix.
Worn idler pulley- cheap and easy fix.
Failed purge valve- chirp coming from gas fill area
Worn out timing chain tensioner guides- bad news of impending doom if not repaired soon.

Grab a friend and isolate the source soon to prevent possible huge repair bills.