Topic: Duties of drivers and pedestrians · Nº 174 / 200
¿Qué puede indicar un humo negro abundante en el escape?
What can a lot of black smoke from the exhaust mean?
- AExceso de combustible en la combustión.Too much fuel in the combustion.
- BFalta de líquido refrigerante.Lack of coolant.
- CDesgaste de los frenos.Worn brakes.
Show answer
Correct answer
- AExceso de combustible en la combustión.Too much fuel in the combustion.
A lot of black smoke from the exhaust pipe is usually linked to poor combustion in the engine. It generally means that the air-fuel mixture is not right, with too much fuel compared to air. This causes incomplete combustion and the release of soot particles, seen as black smoke. It has nothing to do with the cooling system or the condition of the brakes. It is a sign of a possible problem with the engine's fuel supply or injection.
Independent app: not affiliated with or endorsed by the DGT (Spain's Directorate-General for Traffic) or the Ministry of the Interior. The official exam is booked with the DGT and taken at its test centres. The questions here are practice material; the DGT's official question bank is not public.