Black Smoke

Q: What could cause black smoke to emit from the exhaust of my car?

A: Black smoke is usually an indication of the engine getting too much fuel (aka “running rich”). Excess fuel may be entering the combustion chamber. A faulty fuel injector, fuel pressure regulator, PCV valve, clogged catalytic converter, vacuum leak, overdue tune-up, or various engine control sensors could cause the engine to run rich.