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Old 05-14-2011, 09:25 PM
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RSPDiver RSPDiver is offline
Ich bin ein Bimmerer
Location: SC
Join Date: Jul 2004
Posts: 1,241
Mein Auto: 04 ZHP/4
Burning rubber smell: valve cover gasket leak, belts slipping, or other? (with pic)

Okay, so a search yielded some hints to either valve cover gasket failure or belt slippage to some minor but persistant burnt rubber scent either through the air system or ambient (through the windows), but I failed to find any actual pics.

So, I took a pic of what leakage/seepage I saw today while investigating, but wonder if this oil seepage could be it (doesn't seem likely to me) or if it's slippage of the A/C belt (which I rarely run) or the serpentine belt (which is maybe 20k miles newer than the car now at 73k miles) producing smell from slippage. Both appear in decent shape, with no glazing. UUC u/d pullies in place, and the belt is what I received with the pullies. Never noticed the smell until the car was parked for about a week in the cold of the winter a couple of months ago, then ran in the early AM with some faint smoke escaping the hood seams. Occasionally I smell it again, like today with a bit of stop-and-go traffic. No excessive periods of idling (maybe 10 min stop n go).

At this point I'm ready to do the VCG for PM, and get replacement belts also. I guess the real concern would be either tensioner failure, or water pump bearing failure causing some rubbing and smoke.

FWIW, the car still runs like a scalded weasel, with no discernable loss in acceleration, noise comfort, or fuel economy. And the A/C still blows nice and cold. Engine "temps" (on the admittedly buffered temp indicator) run normal to ever so lightly cool.


(pic view from radiator, showing presumed slow seepage from under valve cover)
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Last edited by RSPDiver; 05-14-2011 at 09:44 PM.
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