Knocking noise in idle

[em5712]

Hi everyone, I don't know much about cars so I'm not sure where to begjn with this noise. When I bought my '87 325is, the PO told that the light knocking noise had something to do with an acceleration component (I don't remember his description) and that it could be ignored, but the other day when I turned the car on, the knocking was even faster and a bit louder, it goes away when I press the clutch in or when I get the rpms to about 1,700. The car has a straight pipe but the exhaust smells even worse now and sounds like a harley. Any help would be appreciated.
Thank you.

[Sps]

No worries, it's probably the clutch bearing. Mine does it also. Shant at bimmerheads confirmed it. You will most likely notice it in a drive thru with the clutch out. Its scared me at the In-N-Out drive thru. Push the pedal in and noise goes bye bye.

[em5712]

I'm hoping it is what everyone is saying it is, my mechanic has been closed all weekend so I won't know till Monday

[Sps]

Pull your car up to a block wall on the drivers side and keep the clutch in, put in nuetral, then let the cluth out and you will hear the noise. Push clutch in and the noise should go away. And if it was a rod knock, the noise would get faster as you rev. So I'm pretty sure it's the clutch bearing. I have been told it's common with the e30.

[em5712]

That is what happens when I press the clutch in, and it does go away when I press it in/accelerate, but it got faster overall