OBD-II code · Powertrain (generic, extended)
P25DF A Camshaft Position Control Performance Bank 1
Camshaft phaser A on bank 1 follows the commanded angle too slowly, oscillates, or shows steady-state error outside tolerance. Closed-loop control of cam timing is degraded.
Is it safe to drive with P25DF?
Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.
Common causes
- Most likelyOil control valve spool sticks under varnish
- PossibleStretched timing chain shifts cam reference
- PossibleWrong oil viscosity slows phaser response
Symptoms
- Check engine light on
- Power loss especially in mid-rpm range
- Possible rough idle or stalling
- Increased fuel consumption
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1–5 h
- Emissions test
- Likely to fail
- Parts involved
- Cam Phaser A B1, Oil Control Valve, Cam Position Sensor
Related codes
- P25E2A Camshaft Position Control Performance Bank 2
- P25E5B Camshaft Position Control Performance Bank 1
- P25E8B Camshaft Position Control Performance Bank 2
- P25DCFuel Level Sensor C Stuck
- P25DDA Camshaft Position - Stuck In Locked Position Bank 1
- P25DEA Camshaft Position - Unable to Achieve Locked Position Bank 1
- P25E0A Camshaft Position - Stuck In Locked Position Bank 2
- P25E1A Camshaft Position - Unable to Achieve Locked Position Bank 2
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.