owali

I can’t seem to identify the mysterious noise coming from my engine bay.

It seems like once a day a loud clunking noise comes from my engine when I am in park. Usually the noise will go away after a minute or two. I noticed that if I turn off the A/C the noise will stop immediately.

I got out and followed the noise, it sounds like it was coming from the pulley or wheel the serpentine belt turns associated with the A/C. I can see that the outer ring of the pulley rotates all the time but the inner wheel only rotates when the A/C is on.

Has anyone else had this problem? Any ideas on what I might need to tighten or replace? I am hoping I can fix this without going to the dealer. Thanks for the help.

marshun

loud clunking? so the AC is engaging and disengaging when you have the AC on? does the compressor click on and off when the AC is on?

owali

I only notice the clunking occasionally , but when I do I hear a clunk every time the serpentine belt makes a revolution.

When I turn the A/C on, it stays on, and it works so I think the compressor is working also. However, when it does start clunking if I press the off button on the A/C when the noise starts, the noise will stop.

Do you think it has anything to do with the tensioner pulley?

Additional information: a couple of months ago the guy at oil lube shop changed the serpentine belt, but the noise just started.

UncleRay

iTrader: (2)

Might be your timing belt, fan, or you might just need an A/C service =]

GS_OREO

Sounds like a bad belt tensioner. When the A/c is on it puts an extra load on the tensioner, which may be causing that sound. Get a long screwdriver and place the tip on the tensioner and try to listen to see if it has bad bearings.

owali

Okay, I will try the screwdriver thing, but how will I know if the bearing is bad, what I am listening for?

owali

I am still a little confused about touching it with a screwdriver, can someone please explain?

GS_OREO

Unfortunatly, sound travels to the surrounding areas, so you would have to listen to the noise carefully, and try to isolate the noise.

Try listening to it when your A/C is on, your a/c will cycle on and off, so payattention! You'll know if the bearing is bad if you can hear noise very audible through the screwdriver.

Another thing is try lubing the serpinetine belt. I use WD40, but some people don't like to use it, I still use it anyways.