Technician A says that spark knock (ping or detonation) can be caused by a lean air-fuel mixture. Technician B says that an inoperative cooling fan could cause the engine to spark knock. Which technician is correct?

Question

Quizplus · Accepted Answer

Both technicians are correct. A lean air-fuel mixture can increase combustion temperatures, leading to spark knock. Similarly, an inoperative cooling fan can cause the engine to overheat, also increasing the likelihood of spark knock.

Technician a Says That Spark Knock (Ping or Detonation) Can