My dad and I were working on his 1998 750iL and he jacked the car incorrectly, right behind his right side wheel well. It didn't seem to do any damage, but after we finished working on the car I went to start it.

I got a garage filled with gray smoke, coming out from the tail end of the car. I started it again outside, more gray smoke. I'm not around the car often, but my sister said it's normal looking.

I noticed a rough idle and a puddle of blue liquid after I pushed the car down the driveway.

I need help with this car, as I'm only off school to work on this car for my dad for another day.

you might want to have the rear intakecover or your mass air flow meter those two may be the cause of your problem

Is the smoke coming out of the exhaust or just all around the back? When you jacked it up you might have ruptured the rear self leveling system. This is hydraulic and would do exactly that. ALso, if you broke a break line the same thing would happen.