FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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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 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 , the control module will retard the ignition by a further in stages up to max 13°.
When the engine is fully loaded the ignition is retarded in all cylinders by , 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.