I have a 95 BMW 540i that just got an oil change and filter change but white smoke is coming out the exhaust?
White smoke is usually coolant getting into the combustion chambers, most common is a blown head gasket, but cracked cylinder heads can also do the same thing. Watch you coolant level, if it is blown or cracked it will start to drop and you may also notice an engine miss on initial start up. A block check test can confirm this. HTH
In addition to the previous response, what does your oil look like? If it looks like chocolate milk, there is probably coolant in your oil, and that is another sign of a blown head gasket. That can be checked with a compression test, as well.
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