Replacing the camshaft position sensor on most Mercedes-Benz is relatively easy.
The passenger side sensors are straightforward to replace. However, the driver's side camshaft position sensors are more challenging and will require at least removing the power steering reservoir.
You can replace just the faulty sensor, but it is recommended to replace all four sensors simultaneously.
- A failing camshaft position sensor will start losing its ability to transfer data quickly. As a result, mismatched fuel delivery and ignition timing will cause your engine to sputter, accelerate poorly, lack power, stall, or even start.
- Check Engine Light will come out and throw a P0016 or P0017 code via OBD-II Scanner.
What you will need
- Place the vehicle in Park. Set the parking brakes.
- Allow the engine to cool down.
- Pop the hood by pulling the hood release under the dashboard.
- To gain access to the cam sensors, you have to remove the engine cover and power steering fluid reservoir. You may find the procedure for this at this link.
- Using an e-8 screwdriver with T-handle, remove retaining bolts on intake and exhaust cam position sensors.
- Disconnect the electrical connectors using a flat-head screwdriver.
- Remove the electrical connectors and wires out of the way.
- Pull the cam position sensors out.
- Using a towel, clean the cam position sensor slots to avoid oil leaks after installing new sensors.
- Lubricate the o-ring of each new sensor.
- Place new sensors in place, ensure that there is only one o-ring on each sensor, and remove the old o-rings.
- Install retaining bolts for each sensor.
- Torque the bolts to specs.
- Reconnect electrical connectors to cam position sensors.
- Reinstall the power steering reservoir.
- Reinstall engine cover.
Frequently Asked Questions
How does the cam position sensor work?
- The Camshaft Position Sensor detects camshaft rotation and is mounted near the cylinder head so that the sensor is opposite to the timing rotor attached to the engine camshaft. The engine ECU detects the camshaft angle and performs cylinder recognition based on the signals detected by the camshaft position sensor.
What's the difference between the camshaft and crankshaft position sensor?
- The crankshaft position sensor monitors as a multifunctional sensor used to set ignition timing, detect engine RPM, and relative engine speed. In addition, the camshaft position sensor is used to determine which cylinder is firing to synchronize the fuel injector and coil firing sequence.
How much does it cost to replace the camshaft position sensor?
- To replace a camshaft position sensor, you can expect to pay anywhere from $95 to $200. Parts alone will run about $25 to $100. Labor costs will be in the range of $70 to $100 for professional replacement. Expect to pay more if you have a luxury vehicle or have your local car dealership perform the replacement.