Bank 1 intake camshaft timing is more advanced than the DME commanded - a VarioCam Plus performance fault. On the 987.2 DFI 9A1 engine this generic code is the primary VarioCam timing code (the 987.1 M96/M97 tends to log the Porsche-specific P1340/P1341 instead). Usually oil-flow or actuator related.
SYMPTOMS
- Check-engine light
- Rough idle
- Hesitation
- Power loss
LIKELY CAUSES
- Sticking/clogged camshaft oil-control valve
- Low oil pressure or degraded/wrong-grade oil
- Failed VarioCam adjuster/phaser
- Worn cam-timing components
- Cam position sensor fault
DIAGNOSIS STEPS
- Verify oil level, condition and pressure
- Clean or replace the oil-control valve
- Compare actual vs commanded cam angle in live data
- Inspect the cam position sensor
- Inspect timing components if it persists
RELATED PARTS
- Camshaft oil-control valve
- VarioCam adjuster
- Camshaft position sensor