The crankshaft position system variation compensating values
are stored in the PCM non-volatile memory after a learn procedure has been
performed. If the actual crankshaft position system variation is
not within the crankshaft position system variation compensating
values stored in the PCM, DTC P0300 may set, refer to Diagnostic
Aids for
DTC P0300 Engine Misfire Detected
.
The Crankshaft Position System Variation Learn Procedure should be performed
if any of the following conditions are true:
• | The PCM has been replaced |
• | The engine has been replaced |
• | The crankshaft has been replaced |
• | The crankshaft harmonic balancer has been replaced |
• | The crankshaft position sensor has been replaced |
Important: Set the vehicle parking brake and block the drive wheels when performing
the Crankshaft Position System Variation Learning Procedure in order to prevent
personal injury. Release the throttle when the engine reaches the SECOND
fuel cut off. Leaving the throttle open during the fuel cut off will allow
the engine to decel at an even rate. Once the learn procedure is completed,
the PCM will return the engine control to the operator and the engine will
respond to the throttle position.
Important: The scan tool crankshaft position system variation learn function will
be inhibited if engine coolant temperature is less than 70°C (158°F).
Allow the engine to warm to at least 70°C (158°F)
before attempting the crankshaft position system variation learn
procedure.
The scan tool crankshaft position system variation learn function will
be inhibited if any powertrain DTCs other than DTC P1336 are set before
or during the Crankshaft Position System Variation Learn Procedure.
Diagnose and repair any DTCs if set.
The crankshaft position system variation learn function will be inhibited
if the PCM detects a malfunction involving the camshaft position signal circuit,
the 3X reference circuit, or the 18X reference circuit.
- Set the parking brake.
- Block the driver wheels.
- Ensure that the hood is closed.
- Start the engine and allow engine coolant temperature to reach
at least 70°C (158°F).
- Turn OFF the ignition.
- Select and enable the Crankshaft Position Variation Learn Procedure
with the scan tool.
- Start the vehicle.
- Apply and hold the service brake pedal firmly.
- Ensure that the transaxle is in Park.
- Increase accelerator pedal position until CKP system variation
learn fuel cutoff is reached. CKP system variation learn fuel cutoff is reached
at 5150 RPM. Release the accelerator pedal when the second
fuel cutoff is reached.
- The crankshaft position system variation compensating values are
learned when RPM decreases back to idle. If the procedure terminates, refer
to Important above for instructions.
- Observe DTC status for DTC P1336.
- 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 did not run, check
for other DTCs. If no DTCs other than P1336 are set, repeat the
Crankshaft Position System Variation Learn Procedure as necessary.