Computer-controlled ignition timing is being discussed. Technician A says when excessive wheel slippage occurs, the PCM will advance the timing to increase the torque output from the engine. Technician B says to provide smooth shifting of an automatic transmission, the PCM will temporarily retard the ignition timing to reduce the engine's torque when the transmission is beginning to change gears.
A)A only
B)B only
C)both A and B
D)neither A nor B

Question

Quizplus · Accepted Answer

Technician B is correct. The PCM may retard ignition timing to reduce engine torque for smoother shifting. Technician A is incorrect; the PCM typically retards timing to reduce torque during wheel slippage.

Computer-Controlled Ignition Timing Is Being Discussed