Squeaking sound under hood when engine is cold

[Z4-04]

In my 2004 Z4 with 48,000 miles. I just noticed that when the engine is first started that there is an intermittent whining or squeaking sound. It sounds like its coming from the rubber belt area at the front of the engine near the top - I believe. It might be the belt tensioner? I don't think it’s coming from alternator which sits much lower.

Is there a way to isolate the sound? If it is the belt tensioner, why would it be making noise? Can it be lubricated with grease?

Any suggestions.

 

[ph001]

Length of hose - one end to your ear, the other to the various spinny bits. The bearings have a finite life on the tensioners and all the other pulleys for that matter.

 

[Z4-04]

I actually determined that it is the tension roller next to the alternator. It appears to be a reasonable job to replace it.

Thanks