any help would be great

[C.Saenz]

I just got my 1991 318is a few weeks ago and I'm not sure what this noise is.

The car is from D. Clay, a guy who knew his bimmer inside and out. He put in an m42 from a '95 318ti only a few months ago, so I think he would have set the belt tension properly (though they feel TIGHT). The AC is an e30 unit, but it has an electric fan. The belts look and feel new too. He's the issue.

There is a loud squeal. It isn't always around though. Right after I turn the AC, on there it is (about 50% of the time) and it squeals for a few miserable seconds. The issue isn't only with the AC though, after shifts sometimes it squeals again. This happens most when the AC is on, but the AC doesn't have to be on for it to squeal. So  I don't know if the  problem is bigger than  an AC issue. :mad:

Is this a common m42 issue?
Any recommendations?

Thanks for any help.

[nicknikolovski]

Hi C.Saenz, Turn the A/C on, and immediately put the clutch to the floor, then release, then back down, release, back down for a few times. See if the noise changes.

Like your saying it happens when shifting gears, I am leaning towards a worn clutch release bearing. These squeal and also grubble when worn, but mainly squeal. When actuating the clutch the noise should get louder.

This part is relatively cheap, however while you are in that area, you might as well buy a clutch kit - so clutch disc, pressure plate and release bearing.

[batsbats]

Hi C.Saenz, Turn the A/C on, and immediately put the clutch to the floor, then release, then back down, release, back down for a few times. See if the noise changes.

Like your saying it happens when shifting gears, I am leaning towards a worn clutch release bearing. These squeal and also grubble when worn, but mainly squeal. When actuating the clutch the noise should get louder.

This part is relatively cheap, however while you are in that area, you might as well buy a clutch kit - so clutch disc, pressure plate and release bearing.

If that's the case, might as well go for the m20/323i lighter flywheel swap

to OP: not really sure

[peerless]

Could be something as simple as the A/C Tensioner bearing being worn out. Remove the A/C belt and spin the tensioner pulley, does it make noise or feel rough?

Fairly common and inexpensive and easy to fix.

[C.Saenz]

Thanks guys I'm going to check all these in the coming few days and let you know how it went. I really appreciate it!!