check the throttle position sensor that sits on top of the intake manifold. this happened to my car. i took it off to clean and when i put it back, the car would not run right, apparently it needs to be in a specific position. i took it off an remounted it and it runs fine now.

next potential culprit is the camshaft position sensor. that sits on the driver side cylinder head behind the camshaft pulley.

obviously, checking for codes would be helpful too.

__________________
Ben
1987 190d 2.5Turbo