Crankshaft Position Sensor System Variation Learn Procedure

Crankshaft position system variation compensating values are stored in PCM non-volatile memory after a learn procedure has been performed. If actual crankshaft position system variation is not within crankshaft position system variation compensating values stored in PCM, DTC P0300 may set. See DIAGNOSTIC AIDS under DTC P0300: ENGINE MISFIRE DETECTED.

Crankshaft position system variation learn procedure should be performed if any of the following conditions are true:

DTC P1336 is set.
PCM has been replaced.
Engine has been replaced.
Crankshaft has been replaced.
Crankshaft harmonic balancer has been replaced.
Crankshaft position sensor has been replaced.

NOTE: The scan tool crankshaft position system variation learn function will be inhibited if engine coolant temperature is less than 158°F (70°C). Allow engine to warm to at least 158°F (70°C) before attempting 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 set.

The crankshaft position system variation learn function will be inhibited if PCM detects a malfunction involving the camshaft position signal circuit, the 3X reference circuit, or the 24X reference circuit. If a malfunction has been indicated, perform one of the following tests diagnose system or sensor:

The scan tool crankshaft position system variation learn function will not be enabled until engine coolant temperature reaches 158°F (70°C). Selecting crankshaft position system variation learn procedure on scan tool will command PCM to enable CKP system variation learn fuel cutoff and allow crankshaft position system variation compensating values to be stored in PCM. PCM must detect an engine speed of 5150 RPM during crankshaft position system variation learn procedure to store crankshaft position system variation compensating values and complete procedure.

WARNING: Block drive wheels when performing the crankshaft position system variation learning procedure in order to prevent personal injury. Set vehicle parking brake when instructed by scan tool. Quickly increase accelerator pedal position until reaching wide open throttle and hold. During learn procedure, PCM will automatically control injector operation. When engine has reached a certain RPM, PCM will stop fuel injectors from pulsing until learn procedure is finished. When PCM has learned the crankshaft variation, fuel injectors will return to normal operation and engine will begin to accelerate again. Release throttle when engine reaches the second fuel cutoff. Leaving the throttle open during the fuel cutoff learn procedure will allow the engine to decelerate at an even rate.

Block drive wheels.
Ensure hood is closed.
Start engine and allow engine coolant temperature to reach at least 158°F (70°C).
Turn ignition off.
Using scan tool, select and enable CRANKSHAFT POSITION SYSTEM VARIATION LEARN PROCEDURE.
Set parking brake when instructed by scan tool.
Start engine.
Press and hold brake pedal firmly.
Ensure transaxle is in Park.
Slowly depress accelerator pedal until fuel cutoff is reached at 5150 and hold. Release accelerator pedal after second fuel cutoff has been reached.
Crankshaft position system variation compensating values are learned when engine RPM decreases back to idle.
Using scan tool, observe DTC status for DTC P1336.
If scan tool indicates that DTC P1336 ran and passed, crankshaft position system variation learn procedure is complete. If scan tool indicates that DTC P1336 failed or did not run, check for other DTCs. If no other DTCs are set, repeat crankshaft position system variation learn procedure as necessary.