FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Component Testing

The engine knock sensor is affected by a number of factors. A few of these are: ignition timing, cylinder pressure, fuel octane, etc.

The knock sensor generates an AC voltage whose amplitude increases with the increase of engine knock.

The knock sensor can be tested with a digital voltmeter. The RMS voltage starts at about 2OmVac (at about 700 rpm) and increases to approximately 600 mVac (5000 rpm).
- If the output falls outside of this range a DTC will be set.