Why is my car spewing black smoke out the back?

Answer by  Gabriel (2146)

The smoke is oil being spewed out the exhaust. In all probability your engine is leaking oil into the combustion chamber. Since the oil doesn't burn entirely it passes through the system and out the back. You should first check your oil level (if its happening a lot you're probably low) and then take it to a mechanic.

Answer by  elsewhen (627)

you are probably burning oil... please get that fixed so that we dont have to breate it! its probably a gasket somewhere - some of those are easy/cheap to fix, but the "head gasket" is very expensive, because the mechanic is going to have to take apart the whole engine!

Answer by  HelmerJensen48 (6)

If your car is a diesel it might have some worn gaskets in the fuel pump, if its a gasoline or diesel engine the smoke is most likely to come from worn piston rings or the deduction valve needs to be changed.

Answer by  tamarawilhite (17883)

There are several possibilities. First, your catalytic converter is cracked, broken, damaged, or simply full. Second, your car is burning oil within the engine, which is coming out as black smoke. Third, there is dirt or debris in one of the air hoses, which is burning when the engine is on and comes out as black smoke.

Answer by  Joanie (156)

Your car is spewing black smoke out the back because somehow oil is leaking into the cylinders and is being burned with the gasoline. Most likely either the valves aren't seating properly, which could be for a number of reasons, or the piston rings are worn and allowing oil to leak in along the cylinder walls.

Answer by  Anonymous

take it to a mechanic