P1336
Crankshaft Position System Variation Not Learned
Low· Fix when convenientIntermediatePowertrainManufacturer: GM (Chevrolet, GMC, Buick, Cadillac)
What it means
On GM vehicles the ECU has not learned the small variations in the crankshaft reluctor ring. This is needed for accurate misfire detection and is required after replacing the ECU, crank sensor or engine parts.
Is it safe to drive?
Usually safe. Some vehicles limit engine RPM until the relearn is done.
Symptoms
- Check engine light on
- Engine RPM limited in some cases
Probable causes
Most likely first
- 1Crank relearn not performed after a repair
How to diagnose it
Work through these in order before buying parts
- 1Perform the crankshaft position variation relearn with a capable scan tool.
Common fixes
- Perform the CKP variation relearn
This information is general guidance for the listed makes. Exact causes, specifications and procedures vary by vehicle, so confirm with your service manual or a qualified mechanic before replacing parts.