On-board diagnostic (OBD) systems help mechanics and vehicle owners identify problems that may affect vehicle operation. An illuminated check engine light is often the first sign that an error has been logged in this system. But before any troubleshooting may begin, a scan tool or code reader must be attached to the OBD port to retrieve the specific code.
Code P0025 is an example of a diagnostic trouble code that may come up on your scan tool. This guide will give you basic information on this code’s possible causes, symptoms, and fixes.
What Does the P0025 Code Mean?
Diagnostic trouble code (DTC) P0025 stands for “Exhaust (B) Camshaft Position Timing Over-Retarded (Bank 2).” This code is logged when the vehicle’s primary computer perceives that the exhaust camshaft timing is over-retarded on bank 2.
This generic powertrain code may be set in vehicles of varying makes and models. “B” refers to the exhaust camshaft. Bank 2 refers to the part of the engine opposite the bank containing the #1 cylinder.
To regulate the exhaust camshaft angle, the powertrain control module (PCM) controls the variable valve timing (VVT) solenoid. This solenoid applies oil pressure to an actuator to alter the angle of the camshaft. Changes to the camshaft’s position could lead to the valve timing being advanced or retarded.
The PCM determines exhaust valve timing using signals from the camshaft and crankshaft position sensors and performs feedback control. When the PCM perceives that the bank 2 exhaust cam timing is over-retarded, it sets the code P0025.
Code P0025 is nearly identical to code P0022. Other related DTCs may also be stored with this code (P0010, P0011, P0012, P0020, and P0021).
Vehicles that are prone to code p0025 include various models of Mercedes Benz (especially Mercedes Benz S550), BMW, Toyota, Audi, and Ferrari.
Note: The definition of code P0025 may be different depending on the vehicle manufacturer. Consult the appropriate repair manual or repair database for the exact code definition.
What are the Possible Causes of the P0025 Code?
- Bad variable valve timing solenoid
- Extremely low engine oil level
- Failed variable valve timing actuator
- Worn timing chain
- Damaged PCM or software in need of an update
- Failed timing chain tensioner or guide
- Contaminated oil
What are the Common Symptoms of the P0025 Code?
- Illuminated check engine light
- Poor engine performance
- Excessive fuel consumption
- Rough starting
- Poor idle
- Engine stalling
How to Diagnose the P0025 Code
To ensure that your vehicle stays in top condition, an engine code P0025 must be resolved immediately. However, identifying what triggered this code may be difficult without the right tools or extensive automotive knowledge.
Keep in mind that steps for diagnosis and repair may vary depending on the vehicle’s make and model. It’s best to refer to a repair manual or an online repair database for the appropriate diagnostic procedure. Alternatively, you may seek the help of a mechanic and leave the job to a professional.
How to Fix the P0025 Code
Vehicle owners may misdiagnose the underlying cause of a P0025 code because it shares similar symptoms with other DTCs. Before attempting any DIY fixes, consult a repair manual or an online repair database for factory repair information.
If DIY repairs are not for you, you can always bring your vehicle to an auto shop to get it fixed. You may also refer to these online resources to get a better idea of how a professional might diagnose and resolve this code.
Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic.