Running down an exhaust rattle

[green71]

Hi all,

I'm hoping to locate an exhaust rattle on my '85 318i. Seems to happen anytime I rev it up above 3000 rpm or better. The car is in very good shape and looks great, so it's kind of a drag when the thing's always barking at me whenever I drive it.

Anyway, I recently had the front exhaust section off for a clutch job. I followed the Bentley manual's instruction for diagnosis of the catalytic converter (smack it against a block of wood & listen for rattles) and I didn't hear anything. The PO told me the muffler had been replace fairly recently, too. Alignment and stability are good, too; no shoddy hangers or rubbing, etc.

The one sketchy thing I did find was a loose slip joint between muffler & cat. Could definitely be affecting the system's pressure.

Any ideas on how to go about finding the source of the rattle?

Thanks!