P0025 means Exhaust Camshaft Position Timing Over-Retarded (Bank 2). The exhaust camshaft on bank 2 is more retarded than the computer commanded, or is not reaching its target position. It is a generic OBD-II code, so the definition is the same on any make, but the most likely cause varies by engine; confirm with a scan tool and the service information for your vehicle before buying parts.
What P0025 means
The engine computer uses the crankshaft position sensor to know engine speed and piston position, and the camshaft sensors to know which stroke each cylinder is on. On engines with variable valve timing, oil-driven cam phasers rotate the camshafts relative to the crankshaft under the control of solenoids. Timing codes come from a sensor that cannot be read, or from a measured cam angle that does not match the commanded one, so oil level and condition, sensor signals and mechanical timing all need checking.
P0025 symptoms
- Check engine light
- Rough idle or stalling
- Rattle at start-up on some engines
- Reduced power
Common causes of P0025
- Low or dirty oil, or the wrong viscosity
- Sticking cam timing solenoid or a blocked solenoid screen
- Worn cam phaser
- Stretched timing chain or jumped timing
How to diagnose P0025
- Check oil level and condition first, and confirm the oil viscosity matches the specification
- Command the solenoid with a scan tool and watch actual vs desired cam position
- Check the solenoid screen for debris
- Check cam-to-crank correlation for timing chain stretch
Can you drive with P0025?
Short trips only; a timing chain problem can get worse quickly.
P0025 tips
Check the solenoid screen or filter for debris after an oil change was missed; a blocked screen starves the phaser of oil.
Will P0025 clear itself?
If the fault stops, the computer turns off the check engine light by itself after several drive cycles without seeing it again, and the code stays in memory as history for a while. Clearing P0025 with a scan tool after a repair is fine, but if the cause is still there the code returns, sometimes within one drive. Disconnecting the battery also clears codes on most vehicles, but it erases learned fuel trims and idle settings as well.
Related codes
| Code | Meaning |
|---|---|
| P0015 | Exhaust Camshaft Position Timing Over-Retarded (Bank 1) |
| P0022 | Intake Camshaft Position Timing Over-Retarded (Bank 2) |
| P0024 | Exhaust Camshaft Position Timing Over-Advanced or System Performance (Bank 2) |
Guides that help
When it is more than a sensor
If a stretched chain has already jumped time and damaged valves, or low oil pressure has worn the engine, a repair can cost more than a replacement; see engine replacement cost and compare engines by code on our engines page.
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