06 Cayman S - Rattling Noise in Neutral

[mmhenslee]

Hey everyone,

Last year I purchased a 2006 Cayman S as my gateway drug to Porsches. Yesterday on the drive to work, a rattling/inconsitent noise started coming from the rear of the car that only proliferates itself while A.) the car is neutral, B.) the car is at idle, and C.) the clutch is engaged. If I push the clutch pedal pedal in, put the car in gear, or increase the RPMs of the motor, the noise disappears...

The noise happened again on the drive home when I started the car, disappeared temporarily for about 15 minutes, and then reappeared in the final 5 minutes of the drive home. When I went to start the car this morning to take it to an Indy down the street... the noise had once again disappeared. When the noise does occur, its slightly noticeable inside the cabin (not loud enough to be drowned out by the radio), and is definitely noticeable from the rear of the car when outside of it.

I have a few theories on what it could be, starting with either the pressure plate springs or Input shaft of the transmission (hope not), and of course the disastrous IMS bearing noise, but I would think IMS bearing noise would occur regardless of whether the clutch was in, wouldn't disappear with RPM, and definitely wouldn't just go away with a good night's sleep. I also would think that anything related to the input shaft would increase and decrease with RPM....

Does anyone have input on what the noise could be? If its something simple like a clutch plate, I would just change it myself. If its an input shaft on a transmission, I'm not sure if I could do the work myself or not... If it is an IMS bearing... I don't want to talk about if its an IMS bearing... Any help would be greatly appreciated

[Sil40sK]

Sounds like a failing flywheel.