What does it mean?
P1346 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: VVT Sensor/Camshaft Position Sensor Circuit Range/Performance Problem (Bank 1) .
Symptoms
- Rough idle and a slight surge or shudder when the engine is warm
- Loss of mid-range power and slower throttle response
- Increased fuel consumption on the same driving pattern
- Rattle from the front of the engine during start-up on some engines
- Check engine light on, with variable valve timing or cam correlation codes stored together
Likely causes
- Low or dirty engine oil, which prevents the cam phaser from reaching and holding the commanded angle
- Clogged screen in the oil control valve, restricting flow to the phaser
- Worn cam phaser or a failed locking pin allowing the cam to drift
- Weak or noisy sensor signal caused by an incorrect air gap, debris on the sensor tip or a damaged target ring
- Chafed or loose wiring and corroded connector terminals adding resistance to the circuit
- Timing chain stretch shifting the cam position outside the calibrated window
- Oil control valve solenoid sticking due to varnish build-up
How to fix it
- Check oil level, condition and service interval first, as this circuit depends entirely on clean oil at correct pressure
- Read cam position and the commanded versus actual phaser angle in live data at idle and at raised rpm
- Command the oil control valve with a scan tool and watch whether the actual cam angle follows
- Remove and inspect the oil control valve and its filter screen, cleaning or replacing as needed
- Inspect the cam sensor, its connector and wiring for oil intrusion, chafing and loose terminals
- Scope the cam signal to confirm the pulses are clean and correctly spaced
- Address timing chain wear or replace the phaser if the actual angle cannot follow the command with good oil and a good valve