Powertrain, generic (extended)

P25DD "A" Camshaft Position - Stuck In Locked Position (Bank 1)

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

Many modern cam phasers hold their rotor with a spring-loaded pin at a defined angle, often in mid travel, so the engine starts with stable valve timing before oil pressure builds. P25DD means the intake phaser on bank 1 is still latched at that angle although the controller has asked it to unlock and move, so variable timing is lost on that camshaft. Ford's 2014 code list for the Boss 302S engine carries P25DD as a lamp code next to P25E0, P25E3 and P25E6. BorgWarner describes a passive mid-position lock on Hyundai's Gamma II engine that is released purely by oil flow, which is why thin, dirty or low oil and a sticking control valve are the usual suspects. CARB requires faults that keep the phaser from reaching its target to be detected. Expect weaker pull and higher fuel use.

Likely causes

Low oil level or pressure, or oil of the wrong viscosity, unable to push the pin out
Oil control valve for the bank 1 intake phaser sticking or its screen clogged
Lock pin seized in its bore by sludge or wear inside the phaser

Symptoms

  • Check engine lamp on
  • Less pulling power, especially in the mid-speed range
  • Higher fuel consumption

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

P25DEP25DFP25E0P0011P0010P25CA

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