Need help w/Engine knock solution

[BC11]

I picked up a 911 C4 with an engine noise that sounded just like a failed IMS bearing.

Began IMS replacement with engine in car.

Pulled IMS bearing.

Old IMS bearing does not look or feel bad.


Here is my question - Do I install new bearing at this point? Or drop engine and look for another source of the noise. I was expecting to see a noticeably bad bearing, one ready to fall apart but this one looks and feels good.

Any ideas?

[JFP in PA]

First of all, attempting to replace an IMS bearing in an engine that you think already has a bad IMS bearing is an very bad idea in and of itself.

If you have a knocking engine, pull it and find out what has failed. Throwing parts at an engine making noise is usually a waste of both money and good parts.

[Jake Raby]

Sounds like a failing cylinder. Your location further substantiates this if the car was driven over the winter.

[KRAM36]

Originally Posted by Jake Raby

Sounds like a failing cylinder. Your location further substantiates this if the car was driven over the winter.

This has me curious. I've always had somewhat of what one would think is a knock in the engine. I always attributed this to the "well oiled sewing machine" sound statements that float around here. It's done it since the day I have bought it, 97k miles to 118k miles. Listed to some youtube vids and believe I hear the same sound coming from those engines. Seems more prominent to the drivers side, is this not normal? Zero metal in the oil filter or magnetic drain plug.