I don't know much but white/blue smoke is coolant/water and will smell like coolant. Fuel is supposedly black and smells like fuel. Hope that helps you diagnose. Also it may help to have someone look at BOTH of the exhaust outlets or use a mirror while you rev the engine. Should be pretty obvious?

Sounds like coolant. Check for leaks.

Sorry but where/who can analyze the oil? I have what i think is a small tranny leak. Almost postive, but would like to rule out valve cover gasket leak. I haven't really investigated yet but this caught my interest. What does this analysis cost?!

I'll do it for free.
OIL = black,
trans fluid = red

OK well I was told the only red fluid (at least that leaks red) is the power steering fluid (ATF Dexron 2 or something). Isn't trans fluid pale yellow/straw color that will leak grey (due to metals wearing) ? Used oil is definately BLACK.

Please reference my ongoing transmission leak post:

http://www.xoutpost.com/x5-e53-forum/...rans-leak.html

Steve I owe you. you were there from the beginning. This is a great site. I'll get into details later I have a few pics. Bottom line is "head gasket". I was lucky the head only had to be cut "010" and the block (steel sleeves not seperated from the aluminum block, common problem) was fine except for about three or four head bolt holes. The threads came out with the removal of the head. All 14 holes had to be hand drilled and tapped, then inserts placed in ($1000.00 added).

After few days and things seem fine. I'll have to let it sit a few days and see if I get any smoke at all.

Although I never had it overheat. Don't ever run the X5 too hot. If you get that block too hot, sleeves begin to rise and you are done.

Thanks again.