Hey All,

I'm suffering from a really bad squealing noise at a cold-start. Car is at 130,000 miles, I've changed both belts, water pump, and thermostat. Can't figure out what it is, any idea?


http://youtu.be/n4AT3oEL-no



I took off the serpentine belt and the noise went away, comes back with the belt on. Seems to coming from driver side...

 

Have you tried rotating manually everything when the belt was off (pulleys, alternator, power steering pump, etc)? Maybe something will make that noise. Also check if there is a play in those bearings.
If it's on the driver's side then it may be power steering pump/alternator/pulley.

On the old belt have you noticed any excessive wear in specific parts (i.e. one edge of the belt)?

I also think that you can spray the belt with water to see if the sound would disappear, but double check that one with someone else.
Maybe there's something touching the belt that is not supposed to be there?

Other than that, I have no idea. Good luck!

 

I'd say it's the belt tensioner next to the water pump and just above the alternator:



Part number 2. I've heard of a few that have gone bad for some. Good luck.

 

+1 mind went bad. squeal at start-up.

 

Sounds like the belt tensioner or the bearings in one of your auxiliary units (alternator, A/C compressor, power steering)

 

If that pulley has done 130k, you're on borrowed time. Whether or not that turns out to be the source of the noise, it's time to replace it.

 

Mine was just replaced 3 weeks ago. The belt was 1/3 way off the tensioner. Best part is they didn't even see that when they did an oil change in that morning and told me they'd keep the car overnight so they could hear the noise next morning. Lucky I popped the hood just to look at things during lunch and saw the belt. Wonder if they actually did the oil change ???

It's an 2008 528 with only 50K miles. They also replaced the hydraulic lifters. The car is now quiet at startup. Good thing I have CPO, only paid $50 ded.