993 whine driving me mad
993 whine driving me mad
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Discussion

ULTIMA69

Original Poster:

55 posts

242 months

Tuesday 22nd May 2007
quotequote all
Hi I have a 993 manual C2 varioram model, which I have had for about a month. The car runs well but as speed builds up it developes a very irritating whine, the garage it came from says its tyre noise, I also have a GT3 which on track day tyres doesn't make as much noise.

I suspected wheel bearings but can't find play and the noise does not change as you turn left or right which a wheel bearing normally does as a damaged one is loaded. The drive shafts have no play and all boots are in place and in good order. The wheels are not catching any part of the body work. The tyres are p zeros rears new fronts very worn, tyre pessures correct. Noise does not change from gear to gear or if the car is coasted (clutch in)the noise appears to be road speed related. The car feels like it could do with a geo set but I have not done this yet. Any one else had similare problems or does the 993 really magnify tyre noise? Help



Ballcock

3,855 posts

249 months

Tuesday 22nd May 2007
quotequote all
Could your wife / significant other have become lodged behind the front seats?









sorry ... couldn't resist











ULTIMA69

Original Poster:

55 posts

242 months

Tuesday 22nd May 2007
quotequote all
Er no first thing I checked!

ED965

5,697 posts

253 months

Tuesday 22nd May 2007
quotequote all
Diff????

no can't be gotta be er indoors do another search.

BermyAndy

2,050 posts

248 months

Tuesday 22nd May 2007
quotequote all
is it there when you have your stereo on?

ULTIMA69

Original Poster:

55 posts

242 months

Tuesday 22nd May 2007
quotequote all
Normally diffs are noisy underload (acceleration) if damaged and this just seems to be relating to road speed. In all driving the car is fine it just whines away worst at motorway speeds. Just checked again no significant other in car but she normally whines at higher speed.

ULTIMA69

Original Poster:

55 posts

242 months

Tuesday 22nd May 2007
quotequote all
If you turn stereo on you can't hear the whine provided you have it on loud enough, but I once blew all the big ends out of a transit van by turning the stereo up to cover the knocking its not a solution!

ACEparts_com

3,724 posts

271 months

Tuesday 22nd May 2007
quotequote all
Are they Pirelli asymetricos? When even just half worn they sound terrible; like a couple of empty oil drums for tyres.



Edited by ACEparts_com on Tuesday 22 May 23:47


POORCARDEALER

8,668 posts

271 months

Tuesday 22nd May 2007
quotequote all


ventilation system?



wheel bearing is favourite, I know you have checked but have you had a 2nd opinion, 2 prs ears better than 1?

nel

4,830 posts

271 months

Tuesday 22nd May 2007
quotequote all
I had a similar speed proportional whine on my 993, albeit a 4WD, unaffected by turning, braking, declutching, etc. Turned out to be a gear box bearing though it was 4WD specific as it was the [under-dimensioned] roller bearing on the output shaft to the front wheels. Don't know whether the 2WD boxes have any similar weakness.



When was the gearbox oil last checked/changed? Scheduled change is every 50k miles. In any case, the garage's story of "tyre whine" sounds a bit dodgy to me.

stuttgartmetal

8,164 posts

246 months

Tuesday 22nd May 2007
quotequote all
Aussie import ?

Ballcock

3,855 posts

249 months

Tuesday 22nd May 2007
quotequote all
stuttgartmetal said:
Aussie import ?
hehe

ED965

5,697 posts

253 months

Tuesday 22nd May 2007
quotequote all
Ballcock said:
stuttgartmetal said:
Aussie import ?
hehe
seconded

oldtimer

300 posts

286 months

Tuesday 22nd May 2007
quotequote all
Very likely to be front tyres making the noise. I guess the only way to prove it is to replace them and hey presto noise disappears, however the replacements if same brand and pattern may end up making similar sound when eventually worn down to same level. The individual tread blocks wear more at one end giving a saw tooth effect that you can feel when you run your hand round the wheel.

I had 17 inch Pirelli PZeros on a 993C2 and similar experience , most pronounced at 30-40mph speed range , switched to Contis and problem disappeared.

runner911

627 posts

273 months

Tuesday 22nd May 2007
quotequote all
This may help.
I had Pirelli Assymetricos fitted to my Mk.1 GT3. They were fine when new.
Some time later the car developed a whining noise which increased with speed. It got so bad that I suspected a wheel bearing had given up.
I booked the car into Exeter OPC for inspection.
The technician who services the car identified immediately that it was the rear tyres ( which by this time were all but due for replacing again after only 4500 miles ) which were causing the noise.
Apparently Pirelli Assymetricos do this.
I replaced all four tyres with Michelin Pilot Sport N1's. Problem solved, no more noise.

nervous

24,050 posts

260 months

Wednesday 23rd May 2007
quotequote all
the whine youre hearing is just riccardo endlessly dribbling on about 993 residuals. just ignore it, eventually it just becomes background noise.





kennyboy

641 posts

269 months

Wednesday 23rd May 2007
quotequote all
My guess is Diff.

TOENHEEL

4,501 posts

257 months

Wednesday 23rd May 2007
quotequote all
Maybe somebody fitted a supercharger without telling you!

sleep envy

62,260 posts

279 months

Wednesday 23rd May 2007
quotequote all
nervous said:
just noise
to OP - junk the Pirellis, they're shite

Pickled Piper

6,452 posts

265 months

Wednesday 23rd May 2007
quotequote all
The easiest and cheapest way to eleminate the tyres as a source is to borrow a set of wheels and give them a try. If your tyres are due for a change anyway then try some Michelins.



I've had similar problems on a BMW and was amazed that the noise was eliminated when the garage fitted a set of slave wheels.



pp