Circuit/System Description

The crankshaft position (CKP) sensor is located on the rear of bank 1 of the engine block. The CKP sensor is a hall effect switch that works in conjunction with a 58X reluctor wheel that is attached to the crankshaft. Each tooth on the reluctor wheel is spaced 6 degrees apart with one span having a 12 degree space. The engine control module (ECM) uses the 12 degree space to determine top dead center (TDC) for cylinders 1 and 4. The ECM determines when cylinder 1 is on the compression stroke by monitoring the CKP sensor and the camshaft position (CMP) sensors. The ECM can synchronize the ignition timing, fuel injector timing, and spark knock control based on the CKP sensor and the CMP sensor inputs.