P0025 Fault Code

P0025 OBD-II Trouble Code Short Description

B Camshaft Position - Timing Over-Retarded (Bank 2)

What does trouble code P0025 mean?

The P0025 fault code on cars refers to a problem with the B camshaft position, specifically indicating that the timing is over-retarded on Bank 2. Bank 2 refers to the side of the engine that does not contain the cylinder #1.

The camshaft position is responsible for regulating the timing of the intake and exhaust valves in relation to the pistons' position, ensuring optimal combustion and engine performance. If the camshaft timing on Bank 2 is over-retarded, it means that the timing is not advancing as it should, causing a disruption in the combustion process.

Several potential causes can trigger this fault code, including:

  1. Faulty Camshaft Position Sensor: A malfunctioning sensor can provide incorrect data to the engine control module (ECM), leading to improper timing adjustments.

  2. Timing Chain/Belt Issues: If the timing chain or belt is worn, stretched, or damaged, it can affect the camshaft's position, resulting in over-retarded timing.

  3. Damaged Camshaft: A damaged or excessively worn camshaft can disrupt the timing operation.

  4. ECM Malfunction: A problem with the engine control module may cause incorrect timing adjustments, leading to the fault code.

To diagnose and repair this fault code, the following steps are recommended:

  1. Scan the vehicle's ECM for any additional codes and freeze frame data to gather more information about the issue.

  2. Inspect and test the Camshaft Position Sensor to ensure it is functioning properly. If faulty, it should be replaced.

  3. Check the timing chain or belt for any signs of wear, stretch, or damage. If necessary, replace the timing components.

  4. Inspect the camshaft for any visible damage or excessive wear. If found, the camshaft should be replaced.

  5. If no issues are found with the above components, further diagnostics may be required to identify any ECM problems.

As the P0025 fault code can have multiple potential causes, it is recommended to consult a professional mechanic or use a diagnostic tool to accurately diagnose and resolve the issue.


What are the symptoms of the P0025 code?

The symptoms of a P0025 fault code on cars include:

  • Check Engine Light: The most common symptom is the illumination of the Check Engine Light on the dashboard.
  • Rough Idle: The engine may experience a rough idle or stalling when the fault code is present.
  • Poor Performance: The vehicle may have reduced power and overall performance issues.
  • Decreased Fuel Efficiency: The engine may consume more fuel than usual.
  • Engine Misfires: You may experience engine misfires or hesitation during acceleration.
  • Engine Noise: There may be excessive engine noise coming from the affected bank.

It is important to note that these symptoms can vary depending on the make and model of the vehicle.


What causes the P0025 code?

P0025 fault code refers to "B Camshaft Position - Timing Over-Retarded (Bank 2)". This means that the camshaft position of bank 2 is not advancing as much as it should, causing the timing to be over-retarded.

Several factors can cause this fault code, including:

  1. Timing belt or chain: If the timing belt or chain is loose, stretched, or damaged, it can affect the camshaft timing and trigger the P0025 code.

  2. Camshaft position sensor: A faulty camshaft position sensor can provide incorrect readings to the engine control module (ECM), leading to incorrect timing adjustments and triggering the fault code.

  3. Variable valve timing (VVT) solenoid: The VVT solenoid controls the oil flow to the camshaft, adjusting its timing. If the solenoid is clogged, stuck, or malfunctioning, it can cause an over-retarded timing issue.

  4. Engine oil issues: Insufficient or dirty engine oil can hinder the VVT system's performance, causing timing problems and triggering the fault code.

  5. ECM or wiring problems: Faulty ECM or damaged wiring connecting the camshaft position sensor or VVT solenoid to the ECM can also cause the P0025 code.

It is essential to diagnose and address the underlying cause of the fault code to prevent potential engine damage or performance issues. Professional assistance may be required to accurately diagnose and repair the issue.

Possible Solutions

How to fix P0025?

The P0025 fault code indicates that the "B" camshaft position on bank 2 is experiencing timing over-retarded conditions. This is usually caused by a problem with the camshaft position actuator or the engine's timing system. Here are some steps to diagnose and fix the issue:

  1. Check the oil level and condition: Ensure that the engine has sufficient oil and that it is clean. Low oil pressure or dirty oil can affect the performance of the camshaft position actuator.

  2. Inspect the camshaft position actuator: Check for any signs of damage or wear on the actuator itself. If there are any visible issues, it may need to be replaced.

  3. Test the camshaft position actuator: Use a scan tool or multimeter to test the actuator's electrical signals and verify whether it is functioning correctly. Repair or replace the actuator if necessary.

  4. Inspect the timing chain: Examine the timing chain for any signs of damage or wear. If it is stretched or has any loose or damaged components, it may need to be replaced.

  5. Check the timing chain tensioner: Verify that the timing chain tensioner is operating properly. If it is worn or not providing enough tension, it may need to be replaced.

  6. Inspect the camshaft position sensor: Check the camshaft position sensor for any signs of damage or malfunctioning. Replace it if necessary.

  7. Check the engine's timing: If all other components are in good condition, it may be necessary to verify the engine's timing using a timing light or other diagnostic equipment. Adjust the timing if needed.

  8. Clear the fault codes: Once the issue has been addressed, clear the fault codes using a scan tool. This will reset the check engine light and allow you to monitor if the problem reoccurs.

If you are not confident in troubleshooting the issue yourself, it is recommended to take your car to a qualified mechanic or dealership for further diagnosis and repair.