Accessory Belt Area Rattle [Archive] - GrandAmGT.com Forum

PDA

View Full Version : Accessory Belt Area Rattle


FastlaneV6GT
04-27-2009, 05:05 PM
I can't seem to pinpoint what's causing this rattle. You can hear it the most from under the car and from the passenger side front wheel well area, but also from under the hood. It's easier to isolate the sound with the hood closed due to the fact there are lots of other engine noises that kind of drown it out. It's worst when you're in a smaller area like a parking garage or drive-through. It sounds like valvetrain noise, but I removed the belt and it went away. The belt is fine. Ideas?

I think it may be a pulley, but I also find that hard to believe because if there is tension on the belt, there is tension on the pulley, so there shouldn't be much of a rattle, right? Unless it's a part that's meant to move like the tensioner.

Here's a link to a video I put on YouTube so you can see what I mean:

http://www.youtube.com/watch?v=LJAqUAkceEU

FromTheInside
04-27-2009, 05:14 PM
Try this:

click this link:

http://www.v6z24.com/specs/images/engines/3400v6.jpg

Now, right under the water pump pulley, which is directly next to the coolant bleeder, is a plug if you can see it. (I'm not sure what it is) but under the plug is metal which used to scrape my belt and make noise. You can see its proximity to the belt in the picture. If that does not work, loosen the belt again and inspect your idler pulleys (little black ones) for wear. Look around the belt for something scraping, because the video makes it sound like that.

350rs
04-28-2009, 02:43 PM
does it get worse when you hit the gas? How is the tension on your belt? I would suspect a tensioner pulley. maybe the full assembly. But as said before, check the idler pulleys as well

FastlaneV6GT
04-29-2009, 08:30 AM
does it get worse when you hit the gas? How is the tension on your belt? I would suspect a tensioner pulley. maybe the full assembly. But as said before, check the idler pulleys as well

It doesn't get worse...it does speed up, but then it's harder to hear because of the engine making more "good" noises :-) The tension on the belt is great, and the belt is in great condition.

timberwoof
04-29-2009, 08:38 AM
Sounds like it was when my A/C Compressor was going out.

Try turning on and off you A/C and see if it stops or not. My would do it when it was on then stop when off.

FastlaneV6GT
04-29-2009, 08:47 AM
Sounds like it was when my A/C Compressor was going out.

Try turning on and off you A/C and see if it stops or not. My would do it when it was on then stop when off.

Maybe 6 months? It's a Gatorback. A/C doesnt affect the sound at all.

ITSmyGT
04-29-2009, 10:51 AM
My 3400 was making a squeeking noise started to change all the pullies ie: tansioner, idlers, power steering, came down to taking it to pontiac and they changed the tensioner on it, I guess the one I just bought went bad or was bad from the factory, after that no more noise and sounds great. also check the sides of the belt if there is fraying could be a pulley out of allignment. hope this helps

FastlaneV6GT
04-29-2009, 10:53 AM
My 3400 was making a squeeking noise started to change all the pullies ie: tansioner, idlers, power steering, came down to taking it to pontiac and they changed the tensioner on it, I guess the one I just bought went bad or was bad from the factory, after that no more noise and sounds great. also check the sides of the belt if there is fraying could be a pulley out of allignment. hope this helps

Well like I said above, the belt is great. And the sound is not a squeak...it's a rattle.

FastlaneV6GT
04-29-2009, 11:27 AM
Ok, so this time I didn't take the belt off, but I checked the pulleys with the engine running. The idler pulleys look good, but the tensioner kind of moves around a little too much. I took a screwdriver and pressed against it, and it kind of dampened the rattle just a little bit. So i'm thinking it's the tensioner. It has never been replaced and I have around 122k miles on it. I think I might take the belt off later just to be sure, but for $40 and the fact that's probably it, I think i'll go for it.

ITSmyGT
04-29-2009, 12:36 PM
Sorry, forgot about the belt part...yeah I hope thats it man good luck

ITSmyGT
04-29-2009, 12:58 PM
Yup I just watched your video and thats what mine sounded like but when I hit the gas it would chirp or squeek, tensioner pulley for sure