strange ufo noise
 

I have a wierd slight ufo noise coming from the 944S. I took the front timing belt area a part to trace but it sounds more like under the intake. It only there at idle, and goes away while driving. Main/rod bearing?

shot in the dark. Loose timing belt slapping the covers.

A Big WAG, Vaccum Leak.

Cheers,
Larry

Could be an Injector noise - maybe a clickety clack ???

More like a whirling woo woo woo woo.

Vacuum leak would be my guess, too. There's not much else that could do that under the intake, unless it's the idle stabilizer. Does having the clutch in or out while sitting still change it at all? (torque tube bearings)

I will check for a vacuum leak again. It does not matter if the clutch is in or out, or if its in gear. I removed the front timing cover and ran the car. I noticed the sound a while ago, and used the screw driver to isolate the sound. It was @ the top balance shaft area, so i replaced all the bal shaft bearing. But it did not go away. It does not seem to effect the engine, but would hate to have to rebuild the top again. It does have almost 200,000, and as far as I know the bottom has not been touched.