DTC P1336: CKP System Variation Not Learned: Description
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The Crankshaft Position (CKP) system variation learn feature is used to calculate reference period errors caused by slight tolerance variations in the crankshaft, and the crankshaft position sensors. The calculated error allows the Powertrain Control Module (PCM) to accurately compensate for reference period variations. This enhances the ability of the PCM to detect misfire events over a wider range of engine speed and load.
The PCM stores the 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 the CKP system variation learn procedure must be performed.