Worrisome Engine Noise

[Exphotograher]

Any ideas where this noise is coming from? Thanks. 2005 Legacy wagon with 166k

 

[relative4]

If I had to guess, bad alternator bearing. But maybe no need to guess. Remove alt/PS belt, does noise stop? If so, feel both bearings, see if culprit is obvious. If noise continues, remove AC belt.

[DaveWaters]

I had a similar sound. Thought it was alternator (sounded like the location of the noise). Pulled both belts and hand turned each pulley. The Idler pulley was the culprit. 15 min diagnosis. Easy fix.

[NickCawks]

Definitely could be alternator bearing. Looks like that alternator has been getting wet over time.

 

Also sounds a bit like a power steering pump.

 

Have u tried putting your ear right down to the engine to try and more specifically locate the sound?

 

Whatever it is, a sound from that area of the engine bay is specifically alarming because our cars have interference engines.

 

I strongly suggest not driving the car unless your taking it to a shop for diagnosis.

[DaveWaters]

Btw after pulling the belts off if the problem isn’t evident by hand turning the pulleys, start up the car. If the problem is gone put back the a/c belt first and see if it comes back. If not it’s obviously either ps pump or alternator. If sound remains with no belts on the car... well ... time to look into the timing belt.

[Exphotograher]

Thank you for all of your replies. I have noticed that it is not as loud when ambient temp is warmer but gets louder as the car warms up. ??? I have not done anything to it as I am working on another car now.