Variable valve timing (VVT) is a technology used in the engines of newer vehicles to increase their fuel efficiency and performance. The VVT system adjusts the position of the camshaft(s) in relation to the crankshaft based on the desired torque levels and engine operating conditions. More about that in a minute.
One of the codes that you may find when you retrieve DTCs with your scan tool might be a P000B.
What Does the P000B Code Mean?
Diagnostic Trouble Code (DTC) stands for “Exhaust “B” Camshaft Position Slow Response (Bank 1).” It is triggered when the powertrain control module (PCM) perceives a slow response in the camshaft position phase change from the bank 1 exhaust (B) camshaft.
The code description “B” refers to the exhaust camshaft, while Bank 1 indicates the side of the engine that contains cylinder #1. Note that inline or straight design engines only have one bank.
The PCM monitors the solenoid-operated control valves that direct oil pressure to the hydraulic actuators, which are located between the camshafts and their driving sprocket. The oil pressure changes the angular position (phasing) of each camshaft relative to crankshaft rotation.
The signal relayed by the camshaft position sensor(s) helps the PCM determine the speed and position of the camshaft(s). The output of the crankshaft position sensor is compared against it to determine if the engine is timed properly.
A camshaft position slow response code is set when the actual camshaft position does not match the PCM’s desired camshaft position during phase changes. This OBD code is related to codes P000A, P000C, and P000D.
Understanding how variable valve timing (VVT) systems work could help you address the issue. You can read our advanced, technical explanation of VVT systems.
If you want to learn the possible causes of P000B, read the following section.
Note: The definition of code P000B 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 P000B Code?
- Low engine oil level
- Contaminated or dirty engine oil
- Incorrect engine oil viscosity (use of engine oil that does not meet manufacturer requirements)
- Failed variable valve timing actuator (aka phaser)
- Worn timing chain
- Camshaft position solenoid/oil control valve failure
- Camshaft solenoid control circuit is open, shorted, or has a high resistance condition
- Faulty timing chain tensioner or guide
- PCM issues
What are the Common Symptoms of the P000B Code?
- Reduced engine performance
- Reduced fuel mileage
- Check engine light on
- Rattling noise from the engine
How to Diagnose the P000B Code
Identifying the underlying cause of the P000B code can be difficult, especially if you’re not confident with your automotive knowledge. Consider your know-how and determine if it would be best to seek the help of a professional for an accurate diagnosis.
If you want to diagnose the issue yourself, research what the process may involve. Consult your vehicle’s repair manual or use a repair database to learn more about the P000B code.
How to Fix the Code
The P000B code is a generic trouble code that may apply to various makes and models. While vehicles from different manufacturers may share common symptoms, the process for resolving the code may vary between different vehicles. For instance, the confirmed fixes for a P000B Jeep code may not work as well for a P000B Dodge code.
If you’re an advanced DIYer who’d like to clear this code yourself, refer to your repair manual before starting the troubleshooting process. Search for confirmed fixes that are specific to your car’s make and model from vehicle repair resources.
Products Mentioned in this Guide
Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic.