Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Knock Sensor: Description and Operation

Knock Sensor:





The Knock Sensor (KS) is mounted on the engine and used to sense engine detonation.
The knock sensor is a frequency amplifier with the sensor designed to resonate at approximately the same frequency as the engine knock. This allows relatively large signals to be sent to the Electronic Control Assembly (ECA) without electrical amplification and with a relatively small sensor. The ECA uses this information to alter the ignition timing to optimize ignition timing while reducing the occurance of spark detonation.