Crank relearn procedure 04 2500HD 6.0L

[wthor]

I would like to do a crank sensor relearn on my truck in an effort to resolve a flashing cel (P0300) only when driving over 68 MPH. When I slow down to 62MPH the cel turns off.

I have been told that the use of a computer analyzer to conduct this procedure is not required on my truck since the truck does not have a distributor. This technician told me that my truck automaticaly does the relearn through the ECM as you drive.

Can the GM Technician forum provide any further information on how to conduct a crank sensor variation relearn procedure?

2004 Silverado 2500 HD 6.0 L

[txab]

[Swimmer8366]

I'm have the p0300 come on randomly could be at 1500 rpm could be at 2500,4000 doesn't matter and it doesn't do it all the time only when it wants to drove 7 miles today home from fish fry dinner no light on way there came on three times. Drove same route same way didn't baby it nothing drove normal. Think this would be a thing to try? I've replaced plugs wires injectors fuel filter fuel pump fuel regulator. Swapped coils around. No change. Crank relearn?

 

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[wthor]

Darral,

Thanks for your feedback.

I will have a CKP relearn conducted next week and inform you of the results.

wthor

[wthor]

Had the CKP relearn procedure conducted at a local shop this past week and the flashing CEL (Ramdom Misfires) problem has been solved.

Many thanks again to tbax for your help!!!!!!!

[txab]

I haven't heard of any other way of doing it other than with a scan tool.

 

 

CKP SYSTEM VARIATION LEARN PROCEDURE

 

1. Install a scan tool.
   
2. Monitor the powertrain control module (PCM) for DTCs with a scan tool. If other DTCs are set, except DTC P0315, refer to Diagnostic Trouble Code (DTC) List for the applicable DTC that set.
   
3. Select the crankshaft position (CKP) variation learn procedure with a scan tool.
   
4. The scan tool instructs you to perform the following:
   

4.1. Accelerate to wide open throttle (WOT). 4.2. Release throttle when fuel cut-off occurs. 4.3. Observe fuel cut-off for applicable engine. 4.4. Engine should not accelerate beyond calibrated RPM value. 4.5. Release throttle immediately if value is exceeded. 4.6. Block drive wheels. 4.7. Set parking brake. 4.8. DO NOT apply brake pedal. 4.9. Cycle ignition from OFF to ON. 4.10. Apply and hold brake pedal. 4.11. Start and idle engine. 4.12. Turn A/C OFF. 4.13. Vehicle must remain in Park or Neutral. 4.14. The scan tool monitors certain component signals to determine if all the conditions are met to continue with the procedure. The scan tool only displays the condition that inhibits the procedure.

The scan tool monitors the following components:

• CKP sensors activity-If there is a CKP sensor condition, refer to the applicable DTC that set.
  
• Camshaft position (CMP) sensor activity-If there is a CMP sensor condition, refer to the applicable DTC that set.
  
• Engine coolant temperature (ECT)-If the ECT is not warm enough, idle the engine until the engine coolant temperature reaches the correct temperature.
  

 

1. Enable the CKP system variation learn procedure with a scan tool. 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 responds to throttle position after the learn procedure is complete.
   
2. Accelerate to WOT.
   
3. Release when the fuel cut-off occurs.
   
4. Test in progress
   
5. The scan tool displays Learn Status: Learned this ignition. If the scan tool indicates that DTC P0315 ran and passed, the CKP variation learn procedure is complete. If the scan tool indicates DTC P0315 failed or did not run, refer to DTC P0315. If any other DTCs set, refer to Diagnostic Trouble Code (DTC) List for the applicable DTC that set.
   
6. Turn OFF the ignition for 30 seconds after the learn procedure is completed successfully.
   
7. The CKP system variation learn procedure is also required when the following service procedures have been performed, regardless of whether DTC P0315 is set:
   

 

• 
  
  • A CKP sensor replacement
    
  • An engine replacement
    
  • A PCM replacement
    
  • A harmonic balancer replacement
    
  • A crankshaft replacement
    
  • Any engine repairs which disturb the CKP sensor relationship