Powertrain, generic (extended)

P25E3 "B" Camshaft Position - Stuck In Locked Position (Bank 1)

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

P25E3 concerns the exhaust side: the bank 1 exhaust phaser, camshaft B, remains held by its lock pin when the controller wants to move it. Exhaust timing then stays at its parking angle, which limits how the module can use valve overlap for internal exhaust gas recirculation and scavenging. The Boss 302S OBD-II list Ford published in 2014 marks P25E3 with the warning lamp, alongside the bank 2 exhaust code P25E6. BorgWarner's Gamma II system shows that exhaust phasers can use the same torsional-assist hardware as the intake side, although there only the intake phaser carries the mid-position lock. A pin that stays engaged mostly indicates low or contaminated oil at the phaser, a sticking control valve or a damaged rotor. CARB requires VVT target errors to be detected. The engine may idle roughly, emit more NOx and lose some power.

Likely causes

Low or contaminated oil at the exhaust phaser
Bank 1 exhaust oil control valve sticking
Damaged rotor or lock pin inside the exhaust phaser

Symptoms

  • Check engine lamp on
  • Rough idle
  • Slight loss of power, possibly failed emissions test

Repair estimate

DifficultyHardWorkshop job
Parts and labour€80–1,500
Time0.5–6 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

cam phaser b b1park lock pinoil control valve

Related codes

P25E4P25E5P25E6P0014P0013

References: performanceparts.ford.com, borgwarner.com, law.cornell.edu.