Engine Performance (A8)第 101 / 120 题
A knock sensor allows the PCM to:
a.Measure exhaust oxygen
b.Detect detonation and retard ignition timing to protect the engine
c.Control the fuel pump
d.Read vehicle speed
解析
The knock sensor detects the vibration of detonation so the PCM can retard timing and prevent engine damage. Persistent knock can come from low-octane fuel, carbon buildup, or overheating. A faulty sensor may cause reduced performance or a code.
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