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.
Affected components
- Cam phaser a b1
- Oil control valve
- Cam position sensor
Common causes
- High likelihood: Oil control valve spool sticks under varnish
- Medium likelihood: Stretched timing chain shifts cam reference
- Medium likelihood: Wrong oil viscosity slows phaser response
Possible symptoms
- Check engine light on
- Power loss especially in mid-rpm range
- Possible rough idle or stalling
- Increased fuel consumption
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
Related codes
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.