Powertrain, generic (extended)

P25E7 "B" Camshaft Position - Unable to Achieve Locked Position (Bank 2)

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

With P25E7 the module reports that the bank 2 exhaust phaser could not be brought into its locking position: when the lock is requested, the cam angle does not settle at the parking value or the pin does not hold it there. A start without the pin engaged tends to be rough, and on stop-start engines a smooth restart becomes less certain. No manufacturer documents P25E7 publicly; the closest documented case is P25E4 on bank 1 of Stellantis' Hurricane six, which was resolved by PCM software. Mechanically, mid-lock designs such as BorgWarner's need the rotor to swing past the slot on oil-driven cam torque, so degraded oil, a stuck spool valve or wear in the pin and its bore are usual causes. CARB treats a pin that does not move into position as a VVT fault the OBD system must detect.

Likely causes

Aged or sludged oil slowing the bank 2 exhaust phaser
Spool of the bank 2 exhaust control valve hanging
Worn lock pin or pin bore so the pin no longer holds
Calibration issue fixed by a control unit update

Symptoms

  • Check engine lamp on
  • Rough or rattling start
  • Hesitant restart after an automatic engine stop

Repair estimate

DifficultyHardWorkshop job
Parts and labour€0–1,600
Time0.5–7 h

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

Parts involved

cam phaser b b2park lock pinoil control valve

Related codes

P25E4P25E6P25E8P25E1P0024

References: borgwarner.com, static.nhtsa.gov, law.cornell.edu.