Circuit/System Description

2006 Isuzu Ascender S, 4.2 S, 4WDSECTION Circuit/System Description
WARNING: This page is about a different car, the 2007 GMC Envoy, 2007 Chevrolet TrailBlazer, and 2007 Buick Rainier. However, it is still accessible from the selected car via links, so may be relevant.

The engine control module (ECM) uses the crankshaft position (CKP) sensor and the camshaft position (CMP) sensor pulses to monitor the correlation between the crankshaft and the camshaft position. The crankshaft reluctor wheel consists of a 60-tooth pattern with 2 teeth missing for the reference gap. Each tooth is evenly spaced 6 degrees apart, except for the reference gap. The camshaft reluctor wheel has 4 teeth, 2 narrow and 2 wide. The 4 trailing edges of each tooth are evenly spaced at 90 degrees apart around the circumference of the camshaft sprocket. With the engine running and the CMP actuator in the parked position, the ECM expects the camshaft signal pulses to occur 36 crankshaft degrees before top dead center (BTDC) for cylinder number 1 and every 90 degrees thereafter.

RENDER: 1.0x

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