Help diagnose annoying squeaking noise!
Thread Starter
Melting Slicks
Joined: Feb 2003
Posts: 2,438
Likes: 12
From: Fort Worth TX
Help diagnose annoying squeaking noise!
Here are the characteristics:
-Squeaking/chirping noise is coming from somewhere underneath the hood which increases in frequency proportional to rpms, i.e. there is nothing at idle, but as I give the car some gas a chirping noise gets faster as the rpms climb.
-It is random. Never happens on cold start. I only seem to hear it when the car is already warm.
-Squeaks when moving or stationary, in gear or not in gear (clutch pushed in). However, if for example I go from 1st to 6th getting on the freeway, there is never any noise in 6th gear.
-This morning I heard the noise on the way into work. I came to a stop sign, and when I moved in 1st gear, I accelerated a little harder than my usual "lazy drive to work" pace, and then didn't hear the noise any more.
Any ideas? Could this be as simple as just a belt replacement? Or maybe a tensioner pulley gone bad?
-Squeaking/chirping noise is coming from somewhere underneath the hood which increases in frequency proportional to rpms, i.e. there is nothing at idle, but as I give the car some gas a chirping noise gets faster as the rpms climb.
-It is random. Never happens on cold start. I only seem to hear it when the car is already warm.
-Squeaks when moving or stationary, in gear or not in gear (clutch pushed in). However, if for example I go from 1st to 6th getting on the freeway, there is never any noise in 6th gear.
-This morning I heard the noise on the way into work. I came to a stop sign, and when I moved in 1st gear, I accelerated a little harder than my usual "lazy drive to work" pace, and then didn't hear the noise any more.
Any ideas? Could this be as simple as just a belt replacement? Or maybe a tensioner pulley gone bad?
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
Most likely you are correct that its a belt or idler pulley. Start with the belts and while they are off, spin the idlers and check for quiet operation of them.
Pro
Joined: Apr 2006
Posts: 647
Likes: 22
From: Norwalk CT and Boynton Beach FL
Before you start pulling things apart, find the belt tensioner and spray a little WD40 (or some type of penetrating oil) in the bearing area of the tensioner (both front and back). Also, take a little dab of white grease and put it both on the underside and topside of your belt. Then start her up. I'll bet that ends your squeek. I've done this many times on many different cars and usually works fine. But check your belt to make sure it has no cracks in it ---- if it's old, your best replacing it before it breaks and you get stuck.
Thread Starter
Melting Slicks
Joined: Feb 2003
Posts: 2,438
Likes: 12
From: Fort Worth TX
Thanks for the help guys 
I decided to go ahead and drop the car off at the dealer so they can resolve since I have GMPP. If it's the serpentine belt I'm sure I'm going to have to pay for it anyway since it's a wear-and-tear item. I have a feeling the tensioner pulley has gone bad, though - when I heard the squeaking on the way home, I finally got a chance to pop the hood and take a look and the belt was misaligned on the alternator pulley, causing what I believe was squeaking in the alternator pulley since it was improperly balanced.
I decided to go ahead and drop the car off at the dealer so they can resolve since I have GMPP. If it's the serpentine belt I'm sure I'm going to have to pay for it anyway since it's a wear-and-tear item. I have a feeling the tensioner pulley has gone bad, though - when I heard the squeaking on the way home, I finally got a chance to pop the hood and take a look and the belt was misaligned on the alternator pulley, causing what I believe was squeaking in the alternator pulley since it was improperly balanced.
