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Knock control

Knock control


If knocking should occur in any of the cylinders, the knock sensor will send a signal to the control module. The control module will register in which cylinder the knocking is taking place and retard the ignition by 3°in the cylinder in question.

If the knocking stops through retarding the ignition, the ignition is reset in stages of 0.5° back to the original position.

If knocking should on the other hand continue in the cylinder in question despite retarding the ignition by 3°, the control module will retard the ignition by a further 3° in stages up to max 13°.

When the engine is fully loaded the ignition is retarded in all cylinders by 6°, the purpose being to prevent knocking. When the engine load is reduced, the ignition is reset in stages of 0.5° back to the original position.

Should a break in the knocking sensor or in the sensor circuits occurs, the ignition is retarded by 13° in all cylinders (at engine speeds >2000 rpm) at the same time as the CHECK ENGINE lamp (MIL) comes on.