Circuit Description
WARNING: This page is about a different car, the 2003 GMC Sonoma and 2003 Chevrolet S10 Pickup. However, it is still accessible from the selected car via links, so may be relevant.
The Crankshaft Position (CKP) system variation learning feature is used to calculate reference period errors caused by slight tolerance variations in the crankshaft, the crankshaft balancer interrupter rings, and crankshaft position sensor hall effect switches. The calculated error allows PCM to accurately compensate for reference period variations. The crankshaft position system variation learning feature enhances the ability of PCM to detect misfire events over a wider range of engine speed and load.
PCM stores CKP system variation values after a learn procedure has been performed. This DTC set indicates that the CKP system variation values have not been stored in the PCM and CKP system variation learn procedure must be performed.