Technical and Vehicle Safety
Black smoke from a petrol engine exhaust most likely indicates:
- ○Coolant entering the combustion chamber
- ✓A rich fuel mixture — too much fuel is being burned
- ○Normal condensation on a cold morning
- ○Oil burning due to worn piston rings
Correct answer
A rich fuel mixture — too much fuel is being burned
Black smoke from a petrol engine usually means incomplete combustion due to an overly rich air-fuel mixture, often caused by a faulty sensor or injector.
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