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Engine Crank/Engine Running

ENGINE CRANK/ENGINE RUNNING

During engine crank the PCM will fire 2 spark plugs simultaneously. Of the 2 plugs simultaneously fired, one will be under compression and the other will be on the exhaust stroke. Both plugs will fire until the camshaft position is identified by a successful camshaft position (CMP) sensor signal. Once the camshaft position is identified, only the cylinder under compression will be fired.