ASVAB Automotive Information Operation Practice Test 629498

Question 1 of 5
Combustion

Normal combustion in an engine is initiated by a spark plug and results in the complete burning of the air-fuel mixture. If combustion is initiated by a source other than the spark plug, by a hot spot in the cylinder or combustion chamber for example, pre-ignition results. Detonation results if the air-fuel mixture explodes instead of burning. Detonation can cause extremes in pressure in the combustion chamber leading to engine damage.

Which of the following is the result of combustion being initiated by a source other than the spark plug?

ignition

pre-ignition

pre-combustion

detonation