Engine and gearbox (P)
P0029: Exhaust Valve Control Solenoid Issue
The engine control unit (ECU) has detected that the exhaust camshaft oil control valve on bank 2 is not operating within the expected range. This affects the camshaft timing during tests.
Checked by a licensed car technician · last reviewed 29 September 2026
Symptoms
- Engine warning light on
- Reduced engine performance
- Rough idling
- Poor fuel economy
Common causes
- Oil control valve clogged with sludge
- Low oil pressure
- Wrong oil viscosity
- Camshaft phaser worn
How to check it yourself
- Check engine oil level and condition
- Inspect for oil leaks
- Replace oil with correct viscosity
- Clean or replace oil control valve
Can I keep driving?
The car can be driven, but performance may be reduced.
General guidance, not a professional inspection. Confirm faults with measurements before buying parts, and use a qualified mechanic for brakes, steering, fuel leaks, airbags, and other safety-critical work. Terms and disclaimer