Crankshaft System Variation Learn Procedure

[RedHeartbeat]

The CKP System Variation Learn procedure concerning the relationship of the Crankshaft Postion Sensor, or CKP, to the crankshaft reluctor was introduced in 1997 on some applications and use more broadly in 1998.

DTC P1336 indicates that CKP System Variation is not learned. This learn procedure is needed to compensate for minor variations in manufacturing tolerances that might alter the CKP signal relationship of the crankshaft position sensor to the reluctor wheel, possibly resulting in a false misfire DTC and MIL illumination.

CKP System Variation must be relearned when any of these part are removed or replaced...
1.) CKP sensor
2.) Crankshaft
3.) Engine block
4.) Engine assembly
5.) PCM

If a PCM is replaced without performing the CKP learn procedure, the P1336 will not set and it is possible that a Misfire DTC P0300 might later set falsely. This is due to an incorrect CKP System Variation value being stored in the PCM and being used in misfire calculation.

CKP System Variation is only relearned with a scan tool. It does not relearn on it's own.
1.) Make sure no DTCs are set. If DTCs are set set, service them before performing the procedure.
2.) The service brake must be firmly applied and the transmission in "PARK" for an automatic or "NEUTRAL" for a manual.
3.) The A/C must be "OFF" and the hood closed
4.) At this point, use the Tech 2 and CKP System Variation Learn
5.) Open the accelerator to the identified fuel cutoff speed and release it as soon as the PCM cuts off the fuel and the engine begins to decelerate
6.) The scan tool will identify when the procedure is complete

Diagnostic Aids

If the Crankshaft Position System Variation Learn Procedure cannot be learned, check for the following conditions...
1.) a chipped or damaged reluctor wheel
2.) Incorrect alignment of the CKP sensor to the reluctor wheel
3.) Excessive crankshaft run-out
4.) Interference in the signal circuit to the CKP sensor
5.) Incorrect ratio of crankshaft to camshaft pulses

Functional Check

After performing the Idle Learn procedure and/or the CKP Variation Learn procedure, perform a functional check of the PCM.

1.) Use a Tech 2 to "Capture Info"
2.) Clear Diagnostic Trouble Codes (DTCs), if any are stored
3.) Perform the On-Board Diagnostic System Check
4.) Start engine and let it idle for one (1) minute
5.) Use a scan tool to check for DTCs
6.) Service any DTCs according to service information procedures

[metalchips]

Does HPTuners give you the ability to do a CKP relearn procedure?

[PitchBlackC3]

Not sure about HPtuners, I would think it would since Autoenginuity does.

[RedHeartbeat]

HPTUNERS method to do a Crank Position Learn

Open the VCM Scanner, Select "Displays" "VCM Controls" "Special" tab...
Select the CASE Learn button and follow the instructions



Special VCM Controls

CASE Learn: To use the CASE learn function please follow these steps:

• 1. Put the vehicle into park (auto) or neutral (manual).
  2. Turn off all accessories and A/C.
  3. Apply the parking brake.
  4. Press the brake pedal. Keep the brake pedal depressed during the entire procedure.
  5. Press Begin.
  6. Gradually rev the vehicle to fuel cutoff (around 4000-5000 RPM's) over a period of about 4 seconds. When fuel cuts out, immediately release the throttle.
  7. Allow the engine to come back to an idle.
  8. Turn the ignition off for at least 15 seconds. This step is required for the VCM to store the newly learned configuration.

[SCIV]

Should the thread title read crankCASE or crankSHAFT?

[ethumann]

I have a PCM from Nelson and my engine light came on. I have a HyperTech programmer that I was able to scan and get the code (P0315), which is the Crankshaft position system variation values are not stored in the PCM memory. Unfortunately I live in San Diego, and the only people who have the Tech II scanner is the dealership. They are unwilling to even look at my Chevy Suburban without chrging me a $98 Diagnostic fee. Any advise? Don't suppose my HyperTech Power Programmer III can remedy this problem without messing up the rest of the PCM settings???

[foggy]

you need the tech II tool, or find somebody with HPTuners. Either one of them will work.

[ethumann]

Which Tech II tool? the $8000 one, or the $156 one?

[foggy]

the same one dealership uses

[ethumann]

Have you ever seen this tool? Will this work? Amazon.com: ScanGauge II 3-in-1 Compact Multifunction Vehicle Computer with Customizable Display: Automotive