Powertrain, generic (extended)

P25DE "A" Camshaft Position - Unable to Achieve Locked Position (Bank 1)

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

P25DE is the reverse of P25DD: the intake cam phaser on bank 1 should return to its lock angle and let the pin engage, typically as the engine is about to stop or idles before an automatic stop, but the controller never sees the expected locked position. If the pin is not in place at the next start, the rotor can rattle against its stops and timing wanders until oil pressure takes over. No manufacturer documents P25DE publicly. On mid-lock designs such as BorgWarner's unit for the Hyundai Gamma II, the pin only drops in when the rotor passes the slot under oil-driven cam torque, so a worn pin bore, debris in the phaser or a control valve that cannot reach its lock range are prime candidates. CARB names a pin failing to move to its position among the mechanical faults a VVT monitor has to catch. Symptoms: rough or noisy starts.

Likely causes

Debris or wear in the phaser keeping the pin from dropping into its slot
Oil control valve sticking so the lock range of the spool is never reached
Aged or contaminated oil slowing the phaser at hot idle

Symptoms

  • Check engine lamp on
  • Short rattle or knock from the timing drive right after starting
  • Rough start or unsteady idle in the first seconds

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 a b1park lock pinoil control valve

Related codes

P25DDP25DFP25E1P0011P0016

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