Express 1/2 Ton Van V8-305 5.0L VIN M SFI (1998)
Crankshaft Position Sensor: Service and Repair
Crankshaft Position System Variation Learn Procedure
IMPORTANT: While the learn procedure is in progress, release the throttle immediately when the engine starts to decelerate. The engine control is
returned to the operator and the engine will respond to throttle position after the learn procedure is complete.
IMPORTANT: If the CKP System Variation Learn Procedure cannot be completed successfully, refer to DTC P1336 CKP System Variation Not
Learned for additional diagnostic information. See: Powertrain Management/Computers and Control Systems/Testing and Inspection
1. Install the scan tool.
2. Apply the vehicle's parking brake.
3. Block the drive wheels.
4. Close the hood.
5. Place the vehicle's transmission in Park (A/T) or Neutral (M/T).
6. Idle the engine until the coolant temperature reaches 65°C (150°F).
7. Turn OFF all the accessories.
8. Enable the Crankshaft Position System Variation Learn Procedure with the scan tool.
9. Apply the brakes for the duration of the procedure.
10. Slowly raise the engine RPM to 4000 RPM.
11. Immediately release the throttle when the engine speed decreases.
12. Turn OFF the ignition for 15 seconds after the learn procedure is completed successfully.
