Symptoms of a Bad Automotive Engine Camshaft Position Sensor

Introduction

An automotive engine camshaft position sensor is a simple two wire magnetic sensor that triggers a signal to the engine control module. This information is then used to help refine the engine emissions through data matching and confirm variable camshaft positions as the engine computer advances camshaft timing. In this guide, we'll explore the common symptoms of a bad camshaft position sensor and how to identify them in your vehicle.

What Goes Wrong?

Inside the camshaft sensor there is small gauge copper wiring that is subject to the heat and vibrations, over time these windings can break or short circuit hindering the ability of the sensor to read the magnetic rotation of the camshaft. This can cause the engine to run rough while cruising or at idle, occasionally the engine can enter limp mode.

Faulty Camshaft Position Sensor Symptoms

1. By far, the easier way to tell if the camshaft sensor is bad will be because the check engine light has come on. If you have any of these codes, the camshaft sensor may be bad and need replacement, but not always. If you need help located the camshaft sensor on your car please ask one of our experts to help, it's free.

P0340 - Camshaft Position Sensor Circuit Malfunction (Bank 1)
P0341 - Camshaft Position Sensor Range/Performance Problem (Bank 1)
P0342 - Camshaft Position Sensor Low Input (Bank 1)
P0343 - Camshaft Position Sensor High Input (Bank 1)
P0344 - Camshaft Position Sensor Circuit Intermittent (Bank 1)
P0365 - Camshaft Position Sensor 'A' Circuit Malfunction (Bank 1)
P0366 - Camshaft Position Sensor 'A' Circuit Range/Performance Problem (Bank 1)

False Trouble Code Triggers

While your car may not experience significant issues when these codes are present, there is often an underlying mechanical problem, even if the code indicates a circuit error. The real issue lies in the resistance that the engine computer detects through the sensor, which can be affected if the camshaft is not positioned correctly as intended by the computer.

The most popular causes are:

• Low or dirty engine oil
• Camshaft oil control valve oil screen plugged
• Bad camshaft actuator (phaser)
• Broken or worn timing chain components

Is it Safe to Drive?

When the camshaft angle sensor goes bad, one portion of the information needed to operate the engine is lost. Fortunately, the computer will have enough information from remaining sensors, (crankshaft sensor) to keep the engine running because the computer will substitute alternative values for the missing data. This action causes the engine to loose a small amount of power and fuel economy until repaired.

Service Costs

Camshaft sensor service costs will vary per manufacturer, and depending on the location of the sensor. If you are having the job done at a repair shop or at the dealer it should cost between $280.00 and $450.00. Whereas, if you where doing the job yourself the sensor alone will cost between $45.00 and $95.00.

How Long Do Camshaft Position Sensors Last?

These sensors should last the life of the car, and do in most cases, but as with all electronics they can fail at anytime.

Conclusion

After replacing the camshaft position sensor, the vehicle’s ECU may need to be reset to clear the fault codes. Once installed, the ECU will relearn the sensor’s position, and the engine should return to normal operation.

Watch the Video!

Please watch this video of the job being done to glean additional helpful information.

Credits

This guide knowledge base was created by the 2CarPros Team, and by Ken Lavacot: Automobile repair shop owner and certified master automobile technician of over 30 years. If you have question or need help please ask one of our experts we are happy to help. Please visit our 2CarPros YouTube Channel for additional car repairs.