In Reply to: Exhaust Soot=Oil consumption? posted by Marv B on March 31, 1999 at 08:59:32:
: Folks need your advice. A few postings down Pete mentions cleaning out the soot from his M Roadster exhaust. My M has about 1800 miles and also gets sooty. Will this situation cure itself after the valves fully seat/engine is broken in or is this a common BMW/M trait? I've searched the archives and read the threads regarding high oil consumption and some of the answers provided were a little vague. Since my M is also showing a quart low at this point I assume the oil is finding its way out the exhaust. Need your collective oppinions before I go the warranty/service route. For comparison, my 15 year old GTI has been soot free for 275,000 miles and my 24,000 mile Expedition burns about half a quart every 5,000 miles.
I've got a '99 M coupe that I took delivery of back in October of 1998. My car now has about 7200mi. on it and has been getting better in regards to the oil consumption questions. When it was new I found myself having to put a quart of oil in every 1500-2000mi. This interval has slowed down a bit and now the car requires about a half quart every 2000mi. As the consumption has gone down so has the black soot on my nice shiny exhausts. I've read on the board that the first '99 M model came from the factory with synthetic oil and that because synthetic is so good at what it does, the break-in period on my engine has nearly doubled. I'm down to the last service indicator light, so when the car goes in for service I'll ask BMW about this consumption. However, at this time I'm inclined to believe that this is just normal break-in, and as everything seats, the soot should go away. Some people have taken this matter into their own hands by changing the oil to regular (non-synthetic) oil, and have reported the problem going away quicker during their break-in. But as for me I'm just going to follow BMW's word, suck it up and throw in a couple extra quarts of Mobil 1 as needed. On the plus side !!!! maybe due to the soot, the exhaust note on my car seemed to come out sooner that other people's, and comparing my M coupe with a friends M roadster, my exhaust is noticeable deeper, and just a touch louder. I guess if the soot really bothers you, talk to your BMW dealer, and see what they say about it, and PLEASE keep me posted as to their response.
'99 M coupe