The crankshaft and bank 1 camshaft position signals are out of correlation - a possible cam-timing fault. On the flat-six this points to VarioCam/chain wear, a sticking adjuster, or a cam/crank sensor issue. Persistent correlation faults warrant mechanical timing verification.
SYMPTOMS
- Check-engine light
- Hard start or no-start
- Rough running
- Power loss
LIKELY CAUSES
- Cam timing off (chain stretch / worn tensioner)
- Sticking VarioCam adjuster
- Faulty cam or crank position sensor
- Damaged reluctor wheel
DIAGNOSIS STEPS
- Compare cam vs crank correlation in live data
- Inspect cam/crank sensors and reluctor wheels
- Check oil condition and adjuster operation
- Verify cam timing mechanically if needed
RELATED PARTS
- Camshaft position sensor
- Crankshaft position sensor
- Timing chain / tensioner