Specialist part · #3890 · 1 pts
Which of the following circumstances may indicate bad technical condition of a passenger car?
aEmission of black, blue or white thick fumes.
bEmission of colourless fumes.
cThe engine oil pressure light turning red before starting the engine.
Why?
Thick black exhaust smoke can indicate poor fuel combustion, while blue smoke can indicate burning engine oil. Colourless exhaust gases do not, by themselves, suggest a fault. It is normal for the oil pressure warning light to be on with the ignition before starting, because the engine is not yet producing oil pressure.