Your vehicle’s computer uses input from the crank position sensor to determine where in the rotation top dead center is located. Once it finds top dead center, the computer counts the number of teeth on what is called a tone wheel to calculate engine speed and to know when exactly to fire the fuel injectors and ignition coils.
When this component fails, your engine may run poorly or not at all. The steps provided below for replacing a crankshaft position sensor are similar for most engines. Though on most vehicles the sensor is located at the front of the engine near the crankshaft pulley, there are many different engine designs, so please refer to your vehicle’s factory service manual for detailed instructions on where to find your crankshaft position sensor and any specific service instructions.
Part 1 of 1: Replacing the crankshaft position sensor
Step 1: Prepare the vehicle. Jack the vehicle up high enough to obtain access to the crankshaft position sensor. Secure the vehicle in this position using jack stands.
Step 2: Disconnect the electrical connector. Unplug the sensor’s electrical connector from the engine wiring harness.
Step 3: Locate and remove the crankshaft position sensor. Locate the sensor on the front of the motor near the crankshaft pulley and use the appropriately sized socket and ratchet handle to remove the sensor’s hold down bolt.
Gently but firmly, twist and pull the sensor to remove it from the engine.
Step 4: Prepare the o-ring. Lightly lubricate the o-ring that is on the new sensor to make it easier to install and to prevent the o-ring from being damaged during installation.
Step 5: Install the new sensor. Gently but firmly twist the new crankshaft position sensor into place. Reinstall the original bolt and tighten to the torque specification provided in the factory service manual.
Step 6: Connect the electrical connector Plug the new crankshaft position sensor into the engine wiring harness, making sure that the connector clip is engaged to prevent the sensor from unplugging itself during operation.
Step 7: Lower the vehicle. Carefully remove the jack stands and lower the vehicle.
Step 8: Clearing codes If your check engine light is on, Use a scan tool to read your vehicle’s computer for DTC’s (Diagnostic Trouble Codes). If DTC’s were found during this diagnostic test. Use the scan tools to clear the codes and start the vehicle to ensure proper operation.
By following the guidelines above, you will be able to successfully replace a faulty crankshaft position sensor. However, if you are not comfortable doing the work yourself, a certified technician, like one from YourMechanic, can complete the crankshaft position sensor replacement for you.
This article originally appeared on YourMechanic.com as How to Replace a Crankshaft Position Sensor and was authored by Richard Zeppetini.