OBD-II code · Powertrain (generic, extended)

P25E4 B Camshaft Position - Unable to Achieve Locked Position Bank 1

Camshaft phaser B on bank 1 cannot reach its base position at engine shutdown so the lock pin never engages. Next cold start may run rough until oil pressure builds.

Is it safe to drive with P25E4?

Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.

Common causes

  • Most likelyWorn vanes or housing inside the phaser
  • PossibleSludge or contaminated oil prevents return to base
  • PossibleOil control valve leaks internally

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
1.5–5 h
Emissions test
Usually unaffected
Parts involved
Cam Phaser B B1, Park Lock Pin, Oil Control Valve

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.