GM Service Manual Online
For 1990-2009 cars only

After the powertrain control module (PCM) learns the amount of crankshaft position (CKP) system variation, the PCM stores the compensating values in the non-volatile area of the electrically erasable programmable read only memory (EEPROM). If the amount of crankshaft variation is outside the stored values, DTC P0300 may set. Refer to Diagnostic Aids for DTC P0300 .

The Crankshaft Position System Variation Learn Procedure should be performed for any of the following conditions:

    •  DTC P1336 is set.
    •  PCM replacement
    •  Engine replacement
    •  Crankshaft replacement
    •  Crankshaft position sensor replacement
    • Any engine repairs which disturbs crankshaft to crankshaft position sensor relationship

Caution: Before performing the Crankshaft Position System Variation Learning Procedure always set the vehicle parking brake and block the drive wheels in order to prevent personal injury. Release the throttle immediately when the engine starts to decelerate in order to eliminate over revving the engine. Once the learn procedure is completed, the control module will return engine control to the operator and the engine will respond to the throttle position.

  1. Set the parking brake.
  2. Block the drive wheels.
  3. Ensure the hood is closed.
  4. Start the engine and allow engine coolant temperature to reach at least 70°C (158°F).
  5. Turn OFF the ignition .
  6. Select and enable the crankshaft position variation learn procedure with the scan tool.
  7. Start the vehicle.
  8. Apply and hold the service brake pedal firmly.
  9. Ensure the transaxle is in park.
  10. Increase accelerator pedal position until the fuel cutoff is reached at 5150 RPM. Immediately release the accelerator pedal after fuel cutoff is reached. The crankshaft position system variation compensating values are learned when the RPM decreases back to idle.
  11. Observe DTC status for DTC P1336.
  12. If the scan tool indicates that DTC P1336 ran and passed, the crankshaft position system variation learn procedure is complete. If the scan tool indicates DTC P1336 failed or not run, check for other DTCs. If no DTCs other than P1336 are set, repeat the crankshaft position system variation learn procedure as necessary.