FAQ: Chirp Chirp Chirp - Belt Squeal, Pulley & Tensioner Squeak

Well, just got back from my mechanic. I was having issues with the supercharger tensioner pulley. It was squeeking when the engine was cold. They replaced, I paid, everything was good until I started the next day when the engine was cold. Squeek was still there. Brought it back and they replaced it again. Seems to be fine this time. They are concerned though because when putting the s/c tensioner pulley on, when they tightened it, the squeek started to come from the supercharger snout pulley. Should I be concerned about a major s/c repair? The mechanic is doing some research to see if it is a problem. The mechanic also isn't ripping me off, he done most of the work on my families cars, and we are on a first name basis with him. If anyone can offer some advice on diagnosis or trobleshooting or even repairs, it would be greatly appreciated. Thanks again everyone.

i have never heard a s/c pulley make squeeking noise. not saying your isn't but it could be the water pump right below or the tensioner still making the noise. did you check the oil level in the snout? no s/c repair is "major" a good snout or rebuild should only cost 50-60 and a snout is easy to install. you can buy an entire blower for like 200.
did he replace just the tensioner pulley or the tensioner itself?

The mechanic is pretty sure on the location for the squeek. I just went for a quick drive in it and the engine was cold, I heard a faint squeek when I stepped on the gass a few times, but the temp picked up and it disappeared. It seems to be running fine. My worries have been alleviated a bit. The s/c oil is fine, it was replaced recently. All he did was replace the tensioner pulley and lubed up the nylon bushings underneath the s/c tensioner pulley. The belt is basically new. It is good news that the snout could be fixed for that cheap. That is great news. $200 is no problem whatsoever. I will be talking to the mechanic later this week, so any other information would be great. Thanks for the quick answer.

Mileage?

The car has about 170k on it. It still runs great, save a few repairs....such as this.

i think i have it narrowed down to where my annoying squeak is coming from. it does it all the time, but it changes with rpm and heat. so in the mornings, when cold it, does it at idle. once i get up to temp it only does it at 1700rpm and above. and if i sit in hot weather for a long time it goes away completely if i stay under 2500rpm. i cant hear it ever above 3k but thats probably b/c of too much other noise.

here is what i have done to narrow my search; i tried spraying every moving part (pulleys not belts )with wd40 and then tried white lithium grease. neither made any change in noise. toped off the s/c oil. and pulled off the belts and idlers and checked everything by hand. i cant make the noise happen unless the car is running and the s/c belt is on. all of my pulleys are "new" btw. (less than 20k on the oldest one)

for the tensioner pulley right in front of the supercharger. i upgraded to the 3.5" tensioner pulley, but the noise came way after that install.

with the car running, if i push on the top part of the idler the noise goes away, and if i apply pressure to the bottom the noise becomes worse. if i wrench on the bolt for the tensioner to make the belt fit tighter the noise becomes worse and if i relieve some tension the noise starts to go away. so my guess is the tensioner itself. but it doesnt make any noise when i flex it back and fourth to take the belt off.
so my question is:
1. is there any way to dissemble and clean up the inside of the tensioner or is it a sealed piece i shouldn't mess with?
2. do you think that is where the noise is from or could it still be the s/c, idler, or tensioner pulley? since those are all effected by pressing on the tensioner pulley.
thank you for any advice, its embarrassing rolling through parking lots sounding like a lawn mower with a wet belt.
Matthew

Which tensioner are you experimenting with, the accessory or SC? I have the exact same problem, Matthew. Yesterday I tried changing the accessory idler pulley, but it made no difference. The noise seems to come from that area, so now I suspect the alternator or the accessory tensioner now that you've posted.

s/c tensioner. but i sometimes wonder if its the alternator too, since thats the only thing on that side of the engine i havent replaced.

im going to go out and try to pull it off and see whats wrong.

I have the same annoying skweek but for me it is the tensioner
itself who don't seem to work correctly.

I wonder if the noise is from belt slippage due to worn out tensioner spring?

Maybe for u but shure for me!

my tensioner isnt that old. i remember replacing it with my uncle, back when he had the car. (like 2003 ish) and with the larger pulley i would think the tension is just fine.
also my belt is brand new too. not even 2 months old. (lost it when the lower radiator hose broke)

anyways, i just finished pulling it all apart and cleaning everything i could.
learned a few things too.
1. if you ever need to replace the lower radiator hose. it is much easier to get to by taking off the tensioner and coil packs (basically all one piece). than to try and reach up in there and mess with that rubber clamp.
2. a lot of dirt likes to collect in the cracks behind the tensioner. which probably hold in extra heat. not much but i like to know its clean.
3. the tensioner is all one assembly and i was too afraid of breaking it or having that spring fly at me, so i just cleaned the outside of it and sprayed down the spring.
i will let you know if it squeaks tomorrow when i go to class. its raining out right now :/

For what it's worth, mine started squeaking a couple months ago, almost immediately after installing new belts. Before the belts, I never heard the noise.

Any word on if the tensioner was the issue?

nope. mine still makes lots of noise. i am 80% sure it is the tensioner spring making the noise. but i have no way of fixing it.
i may replace the front pulley again to rule out bad bearing, even tho it is pretty new.

Mine stopped squeaking on its own. I'm certain it's not the pulley, and pretty sure it's not the belt since it's brand new.

I put a new SC belt but I 'm getting a continious squicking noise on a 97 Rev.How can I get rid of this noise?

Iggyy you should start your own thread, but you need to listen with a piece of hose or something to narrow down exactly where the squeak is coming from. It's very common for the idler pullies to go bad. New pulleys are reasonably priced (get the metal dayco ones to replace the OEM plastic ones).

I moved Iggyy's post to this thread, trying to keep pulley squeak info in one location.

okkk.....Boys...how bad is this..
start the car...sounds good..
press gas..no matter what gear...sounds like a bird is yelllinnnnnnnnnnn...ive gotten 3 confirmations its prolly the serpentine belt...it sounded perfect before it went in for the tranny problem..came out..this is what i hear...could they have done something screw it up...i called my dad to see when the serp belt was changed last...it was changed 8,000 miles ago after a bad rainstorm...could they have mis-aligned a pulley causing it grind quickly or rub the wrong way?

now the guy at aamco said if i bought the belt he would install it free...how much does a belt cost? should i get one? where? or anything else i should do.

like always, Thanks genius'

If the belt doesn't look worn or damaged, and only has 8k miles on it, I wouldn't change it just yet. Check belt for lines and abnormal wearing, make sure it is routed correctly, especially on the crank pulley at bottom.

Other causes of chirp are bad idler & tensioner pulleys, and my first guess: squeaky tensioner. Apply +/- torque to the tensioner with engine running to see if noise goes away.

its loud while drivin...

how do i know if a tensioner is going bad/
if it was an idler..wouldnt it make a sound when just i was in park and no gas(torque?) was applied

I had this same problem, the noise was coming from the side with the belt and I thought, is it the belt?, is it the water pump?. I released the tension on the belts and took the belts off. This frees up the pulleys. Then, one by one, I spun the pulleys with my finger and the one with the bad bearings was making noise, loud and clear. So it could be that.

def not the water pump..i had the replaced around the same time as the belt....how bad is it to drive with the noise? the guy said its jus a noise and wont cause damage.

Grab a piece of garden hose to use as a stethescope, and move it around the engine compartment until you find the source of the noise. Bad tensioner or pulley is my guess.