Yesterday when I arrived home from a friends house I noticed that there was smoke coming from the beneath my car (1987 560SEL). I popped the hood and everything looked fine, no smoke, no nothing. It was a hot day (for Northern California, maybe 80 or so), and I had the AC running. The engine temp guage wasn't excessively high, oil pressure was just under 2...basically everything (except for the smoke coming from under my car) was normal. I got down and looked for the source and it looked like it was coming off of the exaust pipes (not out of them, more like if you poured water on hot metal and steam came off the metal). So, what's the deal? Can I safely drive to my shop or should I have the car towed? Thanks in advance for any help!
Justin

Any visible leaks? Are all the fluid levels correct? Is the transmission overfilled? ATF might be coming out the vent and spilling onto the exhaust pipes.

[Edited by Ali Al-Chalabi on 06-20-2001 at 03:36 PM]

Any odors from the smoke?

I have had a couple of occurrences where a piece of trash blowing about on the street would attach to the hot catalytic converter or other exhaust component, and subsequently, melt or burn. Some would leave a residue that would have to be scraped off, while others burned off by itself.

Or even leaking valve cover seals.

Mine were getting bad on the 4.5 before the valve adjustment. At a stop light I could see tendrils of smoke coming from under the car. After doing the valve adjustment and replacing the seals there is no more smoke. Closer inspection of the pipes showed that oil seeping past the seals was slowly dripping onto the pipes from the rear of the head.

I think the oil dripping was the catalyst to get me to adjust the valves. Find the source, oil or transmission fluid dripping onto hot pipes could be a fire hazard.

Thanks for the quick replies! There was no odor from the smoke, even when down on my hands and knees looking under the car I didn't smell anything unusual. My engine oil and ATF levels appear to be okay, however if there is a leak somewhere, I suppose that only a few drops on the exhaust could cause smoke, but not a noticable drop in level. If this problem is "just" a fluid leak somewhere, I suppose it would be okay to drive to the shop, rather than towing. I'll go check for drips under the car...
thanks!
Justin

You undoubtably have an oil leak. (Could have be a plastic bag, though) The answer is definitely to get it in the air and see.

Usually the leaks accumulate on the outside of the pipe where it goes to the center of the car. These pipes are insulated to keep the heat in and often don't get hot enough to do anything but bake the oil. After a longer high speed run they will get hot enough to smoke the oil. I would pay attention but I don't think you will have any problem driving it in, if the speed is kept down and your fluids are OK.

Have you work on the tranny lately? Or filled the tranny oil? That happened to me before and it was the tranny fluid was filled too much. When the car reached operating temp and the fluid expand and leaked. By the time I stopped the car and got down on hands and knees, the leak stopped. A quick check on the stick (from advice of this forum) cured the problem. Good luck.

95 R129
98 W163

I like the comment about "trash". I've had this happen to me twice, and I've seen it many, many times. Those plastic grocery sacks are a BIG problem...

Well, the car has been parked overnight, and I don't see any drips on the ground. So either this is a VERY small leak, or I am the victim of a plastic grocery bag. I guess I'll take it in just to be safe. Again, thanks for all the help.
Justin

Maybe condensation from your AC is dripping down and splashing off your exhaust pipes.