Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSCHEVROLET1999ASTRO VAN 2WD V6-4.3L VIN WREPAIR AND DIAGNOSISRELAYS AND MODULESRELAYS AND MODULES - POWERTRAIN MANAGEMENTRELAYS AND MODULES - COMPUTERS AND CONTROL SYSTEMSENGINE CONTROL MODULESERVICE AND REPAIRCRANKSHAFT RELEARN PROCEDURE
1999 Chevrolet Astro Van 2WD V6-4.3L VIN W
Crankshaft Relearn Procedure
1999 Chevrolet Astro Van 2WD V6-4.3L VIN WSECTION Crankshaft Relearn Procedure
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.
IMPORTANT: If the CKP System Variation Learn Procedure cannot be completed successfully, refer to DTC P1336 CKP System Variation Not Learned.
8. Enable the Crankshaft Position System Variation Learn Procedure with the scan tool.
IMPORTANT: After the ignition switch is turned to the CRANK position, the VCM must see a change in the state of brake switch (Released to Applied) to run the learn procedure. Also, the service brakes, not the parking brake, must be held throughout the duration of the learn procedure.
9. Apply and hold the service brakes.
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.
10. Slowly raise the engine speed 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.
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.
IMPORTANT: If the CKP System Variation Learn Procedure cannot be completed successfully, refer to DTC P1336 CKP System Variation Not Learned.
8. Enable the Crankshaft Position System Variation Learn Procedure with the scan tool.
IMPORTANT: After the ignition switch is turned to the CRANK position, the VCM must see a change in the state of brake switch (Released to Applied) to run the learn procedure. Also, the service brakes, not the parking brake, must be held throughout the duration of the learn procedure.
9. Apply and hold the service brakes.
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.
10. Slowly raise the engine speed 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.
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.