Hello Guys,
There is squeaking / creaking coming from the front engine, fan/belt area, it becoming a pretty annoying! The noise is present after engine started and goes on. I couldn’t pinpoint where squeaking is coming from any specific wheel/pulley.

While the engine is at idle, spray some water to pulley groves and belt (used a squirt bottle). The noise goes a way for 1 or 2 minutes then come back. Anyone know what this could be?

I'm thinking something having to do with the serpentine belt slip issue or tensioner

More hint: Engine runs fine and there are no shaking or vibrate, just squeaking and creaking. Dealer has taken cared harmonic balancer and cat. converter problem 6 months ago, check the serpentine belts have show no damage also no noise came from E-Box fan

All help is much appreciated.
'99 ML320
Mileage: 76K+

Read this thread. If this is your problem, deal with it right away.

Serpentine Belt: Designed to leave you stranded?

Most probably its a loose serpentine belt. I remember my technican dropped some water on my belt whihc was squeaking and the squeaking stopped for a while and he toled me that's how he knows if the squeaking is coming from a loose belt.

Ron in SC and Tablahan
Thanks for all your response.

That is a good point! I will replace the serpentine belt this weekend.
I was wondering if anyone knows how what’s cause the serpentine belt become loose? Due to wear & tear or a bad belt tensioner?…

If after replaced the serpentine belt and squeaking noise still exist I should look further to replace the belt tensioner (low on cash $$$). Is it an easy DIY job? Do you know any place selling only the bearing of tensioner or do I have to purchase whole tensioner assembly?

Again, many thanks to you all.

http://www.trademotion.com/partlocator/index.cfm?action=getLocator&siteid=213951&chapter=EPI346&appSectionid=10&groupid=10007&subgroupid=61856&componentid=0&make=67&model=Ml320&year=1999&graphicID=F346040&callout=22&catalogid=1