Squeaking Under The Hood - BMW Forum

gthoman · 02-23-2005, 02:14 PM

I have a 1999 BMW 323i sedan and there is a squeaking coming from under the hood at idle. It does not happen all the time at idle, but sometimes. I opened the hood and it seemed to be coming from the drive belt, but not sure. I picked up some belt dressing but I'm not sure if this is going to fix the problem. Is there an easy way to find out if a pulley is going bad, or any other problem without taking the belt off, not sure how hard that is?

bad man working · 02-24-2005, 11:57 AM

It's no big problem to take the belt of first draw a map of the way it goes round the pulleys. Then to take off the belt up find the tensioner pulley flick off the cap on the front of the pulley put a 16mm socket on the bolt head in the centre of the pulley and release the tension and slip the belt off

Furious · 02-24-2005, 07:22 PM

yes, like bad man said above thats a very easy way to remove the belt, but to add to it, when you have the belt off you can check your idle pullies and tension pullies by simply giving them a turn, listen to the noise it makes, if one makes a substancial amount more than the rest you might have your problem, however without a trained ear its very difficult to pick the one that may be slightly different. however you didnt specify that its a very loud consistant squeeking so you may just have to deal with the belt.
usually the top idle pully seems to go first (for some reason) pay attention to that one, also check your tension pully as well.

good luck let us know if you need more help and also update us on your findings.

gthoman · 02-25-2005, 09:37 AM

Thanks for the replies......It hasn't squeaked in a couple of days.....Not sure what is going on, but I'll continue to listen and let you know what I find. Hopefully if it starts it wil be this weekend, so I have some time to look into it.....

gthoman · 03-14-2005, 08:04 AM

It seems to squeak when the weather is damp...When I got up this morning, it had rained the night before and when I started the car I heard the squeaking noise...When I got to work it continued to squeak, then it stopped squeaking after sitting idle for about 10 seconds. Does this usually indicate I need to replace the belt? Thanks.....

bryan1970 · 03-14-2005, 09:44 AM

just sounds like water or moisture on the belt. if you live in a really wet environment there may not be a really for sure way to fix it. no matter what if water gets on the belts they might squeek a bit. unless the drive belt has cracks in the groved part of the belt or the smooth side looks like it has been rubbing away then the belt is probablly okay. how old are the belts?

gthoman · 03-27-2005, 01:07 PM

The belts are less than two years old and have about 20,000 miles on them. The sqeaking now seems to be constant. I tried belt dressing and that didn't seem to work, but I don't have real good access to inspect them closely. I have the Bentley manual and took a look and didn't see anything about replacing the belts, just Maintenance. Anyone know how to check the belts, or replace the belts? Could it be anything besides the belts?