Hello, I own a Volvo S60 2001 turbo diesel and the problem is that black smoke is coming out of the cars exhaust, primarily when accelerating. Yesterday I cleaned it out by holding the RPM near the redline and it helped dramatically, however there’s still some black smoke coming out - mostly in the 4th, 5th gear. Sometimes when I drive normally in the 5th gear - the smoke starts coming out of nowhere and I can feel a slight loss of power which anyone else driving the car probably wouldn’t feel. The turbo is working OK and I cleaned the pipe that goes to the EGR - there wasn’t anything in there, surprisingly.

Worth mentioning - I tend to see some white/grey smoke coming out too, mixed in with the black smoke or when black smoke isn’t coming out.

 

are you consuming any coolant or any motor oil? Sounds like the car is running rich...

 

Haven’t really paid that much attention to it - but I remember when one time the oil was pretty low and I was surprised by it. Also might be worth mentioning that another time I saw some oil in my coolant which was really weird, but recently I checked it and didn’t see any oil marks in there.

Any tips on how to check if the car is burning oil and what might be causing it?

 

burning oil can be caused by piston rings, turbo seals, PCV oil separator (flame trap), valve seals. If you pull off the intake air tubing going into the throttle body, do you see any signs of oil? if so then you need to check the PCV and turbo. If that's clean then you'd need to do a compression test on the engine. Not really that well versed in the fuel management for a newer diesel, but I'd suspect its similar to a petrol car where fuel pressure, injector flow, air metering etc can all impact the fuel trim. There you may want to see if you can clean the MAF, throttle body, see if a shop can do a real time scan for how the computer sees the sensor signals etc.