2002 BMW 320 Black Smoke

ALISONFINCH

MEMBER
2002 BMW 320

2002 BMW 320

I have a BMW 320d it recently had a MOT and a few weeks after that black smoke started coming out of the exhaust. In is due an oil service in another 1500 miles. I have checked the oil and it all seems fine. Someone told me that sometimes after an MOT becuase the engine is turnovers a lot and the car is not moving forward it can damage the turbo and that can cause black somke. Any ideas anyone?

2 Replies

RASMATAZ

MECHANIC
75,992 POSTS

Black smoke typical symptoms of an engine that is running rich (too much fuel, not enough air) are poor fuel economy, elevated emissions (Carbon monoxide or CO), and engine may have rough idle or surge condition.

Possible causes include a bad O2 sensor, excessive fuel pressure (bad fuel pressure regulator or plugged return line), leaky fuel injectors, dirty air filter or restricted air inlet, or a defective coolant sensor that prevents the engine management system from going into closed loop mode.