Howdy,
First-off I only recently noticed this, as I never went over 4K RPMs for the first 2K miles, and my C now has 3100 miles on the odo.
Upon hard acceleration (freeway on-ramp), right about when the cam changes profile, a vibration/rattle starts rumbling right behind my left shoulder. When I go to shift from 2nd to 3rd ,at about 6500 RPMs, I notice that the clutch pedal is vibrating like a foot massager when I engage it to shift.
Could the clutch plate be loose? I also notice it clanks if I engage it while the car is accelerating in first gear (parking garage).
Thanks for any wisdom bestowed.
Mine hasn't done that - nor have I heard of anyone else... you should take it into Sonnen and ask them about it - the clank and pedal vibration in aprticular, doesn't sound good.
brad
Thanks beez,
Yes, I will take it in and gain their diagnosis. The clutch has never felt completely whole, so I'll attempt to steer them in that direction. I'm ready for a hatch thunk solution too.
Do check the clutch for the known issues.
The sound of vibration above 5kRPM could be the variocam engaging.
Try to listen to another car while at the dealer to make sure.
Good luck!
w
Please forgive me for scaring the crap out of you, but just from lurking and reading posts around here your symptoms sort of sound like you may be experiencing the dreaded flywheel issue.
It appears that some of the earliest cars were sent out with incorrectly torqued flywheels. Over time, the flywheel bolts would loosen up. At first, this problem would result in weird vibrations and a vague clutch feel. Later, as they loosen up more, the clutch would get to the point where it will not fully disengage, making shifting difficult or near impossible.
What year is your car? I hope this isn't your problem, but just in case it is you may want to familiarize yourself with some of the posts of others who have experienced it. If your car becomes hard to shift, bring it in immediately. Forcing it into gear and driving it like that will wear your syncros.
Take a look at this post:
http://www.planet-9.com/showthread.php?t=2790&highlight=clutch
Resolution
Dusting off this thread to confirm all suspicions.
Rattle behind my head @ >4K RPMs:
Diagnosis/Action
- Left rear quarter window retainer loose and threads damaged. Remove rear interior trim and found left rear quater glass retainer loose and threads damaged. Replace left quater glass and road test.
Vibrating Clutch @ >4K RPMs:
Diagnosis/Action
- Pressure plate springs weak/lost tension and deformed. Remove transmission and found pressure plate springs lost tension. Replace clutch parts (Release bearing, pressure plate, Disk).
They also confirmed the hatch thunk, that Porsche is in denial regarding it, and they have no permanent fix. They also gave away my Stereo manual that I ordered 6 months ago.
My dealership service department, Sonnen, is a pleasure to do business with; as they treat me like an enthusiast and give me the straight skinny on everything. Makes for a very collaborative partnership.
Its back.....
I was so ready to let this thread die, with seeming resolution to my Cayman's maladies; but unfortunately, like Herpes, their back. The clutch pedal has been steadily increasing its level of vibration, especially as the RPMs rise, and the rear window started vibrating again this morning during a >5K RPM blast. Lovely.
I'll have the dealer take another crack at a fix next month when I take it in for its annual oil change. I actually want the clutch vibration to be more pronounced before taking it in, as I think it is still in the realm of a nuance noted only between intimates.
Re: Its back.....
Any updates?
