Help identify this strange noise! 2002 ALH

It is present when the car is cold only. It is also accompanied by an odd whooshing sound during deceleration.

http://www.youtube.com/watch?v=14gkO39n_k8

Sounds like one of the timing belt rollers making noise, or perhaps the serpentine belt tensioner or idler pulley. The timing belt noise when cold is a pretty common thing. I had two belts that did that on my ALH. You may want to remove the timing belt cover and see if you an pinpoint where the noise is coming from. Sometimes it occurs when debris gets on the back side of the belt and rubs off on a roller. Then the roller will make noise when the stuck debris passes over the belt.

How far into the change interval are you? If you're nearing a belt change time you might want to go ahead and do it. If you're not and none of the rollers or tensioner sound like they have bad bearings, then you could let it go. I didn't change my belt early when it happened, and didn't have a problem. But in this case, past performance is no guarantee of future returns.

Good input. I’m 90k into my next change due at 300k. I was initially thinking a piston ring and lost compression as I thought that would explain the noise during decel.

But that wouldn’t make sense because it’s still incredibly powerful with absolutely no power loss. New t-belt it is then. Thanks!!

Indigo, as I approach 300k, should I just bite the bullet and get the high mileage kit with all the fixins’? Including engine mount, both pulleys, etc?

It depends on how you've maintained the car. If you've never replaced the front mount, I'd do that. Otherwise the high mileage kit is a good option if you've not replaced the additional components recently. If you have, you're better off with the regular kit and the tensioner and roller studs.

Just to confirm, you don't suspect a compression/piston rings issue based on this sound?

absalom said:

Indigo, as I approach 300k, should I just bite the bullet and get the high mileage kit with all the fixins’? Including engine mount, both pulleys, etc?

Click to expand...

The cam gear is recommended at 300K miles.

absalom said:

Just to confirm, you don't suspect a compression/piston rings issue based on this sound?

Click to expand...

I don't hear anything that suggests a compression/rings issue.

It sounds like it's coming from the back? Maybe an exhaust leak? It sounds like something timing or top end related. I had a similar noise to this just this morning. It was a poorly seated injector in my case.

Sounds like the accessory belt. Mine made a very similar sound until I changed to a different brand. I forget which was which.