georgie

Odd noise coming from seemingly clutch transmission. At standstill, putting the car in first (or reverse for that matter) I'm getting a low whine or "rrrrrrrrrrrr" sound as I release the clutch pedal. The car does this unpredictably. Seemingly when the car is hot, the noise goes away. When the car is say halfway through initially heating up is when it's most likely to make the noise. And more often than not, when I'm at a standstill on an uphill slope and then engage the clutch it makes the noise. Like it's doing it when it's under heavy load.

I'm wondering if it could be a transmission mount of some sort? It makes this noise/vibration and then in most all cases it causes the catalytic heat shield coincidentally to vibrate and make a slight racket of noise.

Anyone, any ideas? It's more than annoying.......I'd love to find out what it is.

Thanks!

John Boggiano

Does your clutch work OK?
Not slipping, nice, smooth action?

Thomas Linser

Hi Georgie

OK your clutch noise can be a lot of things.

1) DMF breaking
2) Normal transmission noise
3) LWF noise with accompaniyng normal transmission noise

The first thing I would check with a porsche specialist is if the car is still equiped with the so called double-mass-flywheel a.k.a as "DMF", if yes those are DMF's prone to failure and have to be replaced...yes I know... it's annoying and quite expensive

If you are Lucky and you do not have any DMF problems then it can be the normal transmission sound of the gears vibrating against each other. The sound is not really a problem since it's absolutely normal...but OK it sound a bit coffee grinder, and it's not quite the sound you expect to hear from such a car. This sound is caused by the fact that in this case i.e. without DMF, you have a single mass flywheel as had the RS or the cup car in their time of production (this item is much lighter than the DMF and thus logically called Light Weight Flywheel or "LWF")
The LWF makes the engine quite responsive and free-revving but...yes.. there is always a but...the lighter mass of the flywheel provoques a erratic idle which can also provoque the engine to stall. You have to compensate the erratic idle with a remapped DME or ECU (Engine Controll Unit) chip unit that will solve, in most cases anyway, the problem.

The DMF Double Mass Flywheel was built to compensate the coffe grinder sound of the transmission, i.e. to make the car less noisier and acceptable for the Posch Porsche Drivers (PPD)

So you see the problem can be multiple and not so easy to locate. For more infos make a search under Clutch, DMF, and LWF I'm quite sure that you will find a lot of usefull hints...

My advice would be to go to a Porsche specialist and let the car check...

Hope this helped a bit and

Grüetzi THOMAS <img border="0" alt="[byebye]" title="" src="graemlins/wave.gif" />

georgie

Thomas,

Thank you for the great description! This year does not have the DMF fortunately. The 89 does not have the problematic flywheel. Yes, it sounds a bit like a coffee grinder. I'll run it by a specialist and see what they think they hear. Thanks again for the lengthy explanation.

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John,

The clutch otherwise works absolutely perfectly. No slippage, no chatter. Hi revs or low, now slippage whatsoever. I've tried to make it slip even and it won't.