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.
Medium severity. Can I keep driving?Drive little and gently. If you hear timing chain noise or the oil light comes on, shut off the engine.
Bank 1 is the side of the engine with cylinder 1. Inline engines only have this bank.
Symptoms
- Check engine lamp on
- Rough idle
- Slight loss of power, possibly failed emissions test
Most 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
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: hard
- It can trigger limp mode.
- It affects emissions.
What each character of P25E3 means
- P: Powertrain: engine and transmission
- 2: Generic code: same on every make
- 5: Speed and idle
- E3: Specific fault in that system
Frequently asked questions
Can I keep driving with code P25E3?
Drive little and gently. If you hear timing chain noise or the oil light comes on, shut off the engine.
What causes code P25E3?
The most common causes are: low or contaminated oil at the exhaust phaser; bank 1 exhaust oil control valve sticking; damaged rotor or lock pin inside the exhaust phaser.
Related codes
- P25E4"B" Camshaft Position - Unable to Achieve Locked Position (Bank 1)
- P25E5"B" Camshaft Position Control Performance (Bank 1)
- P25E6"B" Camshaft Position - Stuck In Locked Position (Bank 2)
- P0014"B" Camshaft Position - Timing Over-Advanced or System Performance (Bank 1)
- P0013"B" Camshaft Position Actuator Circuit (Bank 1)
Sources
- performanceparts.ford.com: 2014 BOSS 302S OBDII Codes
- borgwarner.com: borgwarner s vct technology with mid position lock
- law.cornell.edu: 13 CCR 1968.2
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.