TR6

Tried a quick search but turned up nothing useful. I've only owned this car (93 RSA) for a few days and have noticed the following. After driving it to work and back in a combination of revving/accelerating hard and also a lot of sitting in very hot stop and go traffic, there is a fine dark residue on the rear bumper and deck lid that appears to be a very fine mist of what I think is condensed oil vapor(?). Its more noticeable because its a white car. Has anyone seen this before? Is it indicative of a problem that I need to be aware of? The car leaks the usual couple of drops of oil when its parked, but doesn't appear to be leaking large amounts of oil. However, while I was sitting in stop and go traffic yesterday evening, I did notice a barely visible cloud wafting past me that smelled of oil vapor.

AOW162435

I may be way off, but make sure your alignment is correct. I drove my new-to-me '95 993 from Seattle to Baltimore last year with pretty bad alignment. This was unknown to me at the time of departure, but a few days into the trip, I started noticing a fine black dust all over the rear of the car. By the time 3,200 miles had elapsed, the front tires were shot from a toe-out condition, and the rears were quietly scrubbing along, creating the residue from a minor toe-in setting.

Andreas

axl911

You should be able to tell if it's oil or tire residue. If it's oil, then the stuff on your bumper would be greasy and oily. If it's tire, then it should be dry.

Now if it's oily, you need to check to see whether the car is smoking or where it is smoking.

Hopefully, it's not smoking at idle when the engine is warm.

Colin 90 C2

I think it must be oil leaking. I also have a white car and have noticed the same condition. It usually accumulates above the license plate too. You need to get your car up in the air and track down the usual suspects, ie. power steering seal, oil pressure sender, oil breather, oil hoses, cylinder leaks, etc. Once you have narrowed the leak down, you can put together a plan to fix.

Or, you can put on a good coat of wax and wash often.

Kavo

I had the same problem with a ’91 C2 that I owned. I found the oily residue after some hard acceleration or a day on the track. My problem was the paper gasket that is behind the cam chain boxes. It is a small gasket with three holes in it. I had to remove the motor and disassemble the top end enough to remove the cam chain boxes. The hardest part of the job is timing the cams when reassembling everything.

Heirsh

Same problem here. mine is around the tailpipe so i think its coming from oil in the exhaust. I dont have much consumption so I dont worry about it. Could be a leak though, I dont have any drips so I just never considered it.

TR6

That may be what's causing my problem. I've gotten addicted to accelerating hard up to redline out of the toll booths the last couple of days. Would that cause it to spit out oil?

TR6

Its definitely oily.

axl911

TR6,

Does it leak oil? Is it wet on the bottom of the engine?

Does is smoke?

C4Russ

I have a GP White C4. It doesn't smoke, uses less then a quart per 3000 miles and also has this residue on the rear of the car. It's not tire, it's hot exhaust. I've seen this on other P-cars and see no reason to believe this is out of the ordinary. I think it is easily spotted on the whilte paint.

TR6

yes, a few drops everytime its parked in the garage
Not 100% sure. I don't think its burning oil internally, however I think that there is some oil vapor smoke from oil on the outside of the engine. You can definitely smell it, but I've been told that is part of the 911 charm.
Some on the exhaust pipes and crankcase. See photos. I don't know what is considered "normal". In comparison, my TR6 has more oil on the bottom of the engine, but my BMW M Coupe is bone dry. I think the problem here is that the oil is ending up on the hot exhaust which of course will vaporize it. Maybe I need to get it up in the air and give it a good degreasing.

Chad T

Could it possibly be oily condensation blowing out? The exhaust gets very wet inside until it is warmed up.

P.S. Thanks for starting another thread. I was getting sick of that John Cougar Menstral-cramp song in my head.

Congrats on the new car!

wsybert

Mine does the same thing. '90 C2. I get about 3 small spots on the floor overnight after a hard day driving. I know my left cam chain cover is leaking. I think it is just oil blowing off the bottom of the car and coming up onto the bumper. Mine is noticable on the left side top of the bumper. (oil spots on the floor are on the left side too.)

Trio

I had the same problem as Kavo and it produced the symptoms you describe. I had a blown cam cover gasket, and the leak got into the fan which then proceeded to blow a fine oily mist all over the back end of my car. Replacing the cam cover gasket solved the problem.

By the way, if you would change your oil a little more often, you would get a golden colored residue instead of the black you describe ...

Chad T

I just noticed my car has a bit of this residue since I left the undretray off after installing an exhaust. Hmmm. Might have to check the garage floor to see if she's marking her territory.