Crankshaft Position Sensor
Modern engine management systems employ a crankshaft position sensor or CPS to keep tabs on the position and speed of the crankshaft. Based on the readings, the sensor then yields an alternating signal, which is used by the engine management computer to either maintain the current engine setup or make necessary adjustments to ensure smooth engine operations.
But much like other mechanical automotive components, the CPS will start to malfunction over time. Once it weakens, the engine management computer will receive inaccurate signals, so it won't be able to fine-tune ignition timing and other elements necessary for the proper operation of the engine. As soon as you notice ignition backfiring and stalling, as well as vehicle hesitation under acceleration, have your crankshaft sensor checked immediately.
If after troubleshooting you found out that the CPS now needs replacement, you can follow these steps on how to replace crankshaft position sensor:
What you'll need:
- New o-ring
- Paper spacer
- Socket wrench
- Vehicle manual
- New crankshaft position sensor
Step 1: Put safety above all.
Park the vehicle on a solid, level ground and engage the parking brake. Allow the engine to cool down completely.
Open the hood and disconnect the vehicle's negative battery ground cable before starting with the replacement process. You see, the battery stores big amount of energy, and if you fail to disconnect it, you may experience accidental shocks that could possibly result in injury or damaged electronic component.
Step 2: Locate the crankshaft position sensor.
Here comes the tricky part because the location of crankshaft position sensor may vary from one vehicle model to another. To find the exact location of the CPS in less time and effort, consult your owner's manual. In some vehicles, this sensor is situated in front of the engine, by the main pulley. There are also cases when the CPS is placed at the side or at the rear of the engine.
Step 3: Take the crankshaft position sensor out.
The CPS is usually held in place by a single retaining bolt and a wiring harness. Work with the wires first. Memorize how the wires are connected to the sensor or take a picture of them, so you won't have a hard time reconnecting them later once the defective sensor has been replaced.
Once the wires have been detached, get the socket wrench and start prying the bolt out. With the bolt removed, you can now take the defective sensor out.
Step 4: Install the new crankshaft position sensor.
The sensor is sealed with an o-ring that you also need to change every time the sensor is replaced. Don't make the mistake of using the old o-ring or you'll just end up repeating the installation process only to replace the old o-ring that you've reused. Get your new o-ring and place it around the sensor. Position the new sensor, along with the o-ring, on the same spot where the old unit was installed.
Step 5: Reconnect the wires.
This is where your sharp memory or the picture that you've taken will come into play. Make sure that the wires are reconnected in the same order as they were before the installation. After this, the unit will normally lock into its place; if it does not, then you have to do manual adjustments. Do so using a paper spacer. Once the sensor is secured in place, reconnect the battery cable and shut the hood.