The crankshaft position sensor is an important component used in modern engines. This sensor plays an important role in the efficient operation of the engine.
This sensor monitors the engine crankshaft speed and position based on magnetic waves and informs the vehicle’s ECM. Based on this information, the ECM manages the proper fuel mixture and ignition timing for engine operation.
But sometimes, when the crankshaft position sensor gets damaged, it starts causing many problems related to the engine. Often in this situation, people start thinking of a temporary fix for the crankshaft position sensor so that the cost of its replacement can be avoided.
Temporary Fix For Crankshaft Position Sensor
A temporary fix for the crankshaft position sensor, reset the CPS sensor by disconnecting the battery negative cable for 5 to 10 minutes. Additionally, check the CPS sensor wiring, clean any debris or dirt from the CPS sensor, reinstall it, and try starting the vehicle.
1. Inspect The Sensor
The crankshaft position sensor is located in the engine block close to the crankshaft, which may cause the sensor to become dirty or covered with oil and cause this sensor to malfunction or fail.
2. Clean The Sensor
Disconnect the sensor’s electrical connector and clean the sensor for any signs of contamination or debris. For this, you clean the sensor using a suitable electrical contact cleaner and a soft cloth.
3. Check Wiring and Connections
Make sure the wiring and connections associated with the crankshaft position sensor are correct. Because loose connections, worn wires, or corroded terminals can interfere with the crankshaft position sensor’s function.
If any problems are found with the wiring and connections associated with this sensor, repair or replace the damaged wiring and connections.
4. Reset Fault Codes
If a faulty crankshaft position sensor triggered the engine warning light or error code, you can reset the fault code related to the crankshaft position sensor.
Use an OBD-II scanner or code reader to clear the error code. Although this is a temporary solution, these error codes may reappear if your vehicle’s crankshaft position sensor or wiring is damaged.
What is A Crankshaft Position Sensor
The crankshaft position sensor in the engine is an important component of the engine management system. The crankshaft position sensor monitors the position and speed of the crankshaft in the engine, and this sensor sends signals to the ECM to control fuel injection and ignition timing.
The crankshaft position sensor is usually a smaller component. This sensor works on a magnetic wave to detect the position and speed of the crankshaft while the engine is running.
The CPS sends a sensor signal to the ECM, which uses it to determine when and how much fuel mixture to send to the engine, and the ECM determines ignition timing based on this signal.
Crankshaft Position Sensor Location
The location of the crankshaft position sensor usually depends on the model and size of the vehicle. But in most vehicles, the crankshaft position sensor is installed near the crankshaft.
In many vehicles, the crankshaft position sensor is mounted above the timing cover, and in some models of vehicles, the crankshaft position sensor is mounted on the rear or side of the engine.
In some vehicles, the crankshaft position sensor is mounted on the transmission bell cover. So that it detects the rotational speed of the engine through the flywheel of the clutch plate and provides a signal about the rotational speed of the engine to the ECM module unit.
What Does The Crankshaft Sensor Do?
Crankshaft position sensors are used in modern engines, both diesel and gas-powered. The crankshaft position sensor usually works on the basis of a magnetic field.
This sensor is mounted near the crankshaft of the engine and sends a signal to the vehicle’s ECM to monitor the position and speed of the crankshaft.
As the engine’s crankshaft rotates, this sensor monitors the speed and position of the crankshaft via magnetic waves. and sends a signal of the crankshaft position and speed to the engine control module.
The ECM controls fuel injection and ignition timing based on this received information, ensuring proper fuel mixture ratio and timing to keep the engine running smoothly and efficiently.
In fact, based on signals received from monitoring crankshaft position and speed, the ECM adjusts the firing order of the fuel mixtures to ensure that they are firing at the correct times.
Symptoms of A Bad Crankshaft Position Sensor
When the crankshaft position sensor of any modern engine fails, you can see different symptoms related to it.
- Engine Warning Light Appears: Often, the first thing you will see when a crankshaft position sensor or other sensor fails is a warning light in your vehicle’s cluster meter.
- Engine Starting Problems: Whenever the crankshaft position sensor of your vehicle fails, you will find it difficult to start the engine.
- Engine Intermittent Stalling: Intermittent engine stalling can also be a symptom of a failing crankshaft position sensor.
- Engine Uneven Acceleration Problem: If your vehicle’s engine somehow starts when this sensor fails, it will cause an uneven acceleration problem.
- Engine Misfiring Issues: Often, you will see misfire-related issues when the crankshaft position sensor is not working properly.
- Engine Rough Idle: You will see rough idle problems if the crankshaft position sensor fails.
- Poor Fuel Mileage: The crankshaft position sensor can result in poor fuel mileage for your vehicle.
- Poor Engine Performance: Failure of the crankshaft position sensor can badly affect the power performance of the engine.
How To Reset Crankshaft Position Sensor Without Scanner
Resetting the crankshaft position sensor without a scanner can be a bit tricky because the vehicle diagnostic (OBD) system may be difficult to access during the process. However, there are a few simple steps you can try to manually reset crankshaft position sensor.
1. Disconnect the Battery
The first thing you should do is disconnect the negative terminal of the vehicle’s battery. This process will disconnect power to your vehicle’s CPS and other electronic systems.
2. Locate The CPS
Often, in vehicles, the CPS is located near the crankshaft pulley or flywheel/flexplate. Check your vehicle’s service manual to find it.
3. Remove the CPS
After this, you will need to separate the crankshaft position sensor from the engine in order to reset it. The CPS removal procedure may vary depending on the vehicle.
4. Inspect & Clean The CPS
Next, check the CPS for any dirt, debris, or damage. Use a soft cloth or brush to gently clean the sensor and also inspect the wiring connected to the CPS.
5. Reinstall The Crankshaft Position Sensor
After inspection and cleaning, install the CPS back into the engine and properly connect the CPS wiring connectors.
6. Reconnect the Battery
After this process, reconnect the negative terminal to the battery and tighten the battery terminal.
7. Start the Engine
Next, start the engine of the vehicle and check the engine’s performance. In some cases, simply disconnecting and reconnecting the battery may reset the CPS, unless the crankshaft position sensor is completely worn out or the wiring is damaged.
How To Reset Crankshaft Position Sensor With Scanner
To reset the crankshaft position sensor with an OBD scanner, you have to repeat the following process:
1. Connect Scanner Tool
First, connect the OBD-II scanner to the diagnostic port of your vehicle. The diagnostic port is usually located under the dashboard, near the vehicle’s steering column. However, in some vehicles, the diagnostic port is also located under the dashboard on the passenger side.
2. Turn on The OBD Scanner
Turn on your vehicle’s ignition, but do not start the engine. Then turn on the OBD scanner by connecting it to the diagnostic port of the vehicle.
3. Access The OBD Menu
Navigate through the scanner’s menus to find the OBD-II, or Diagnostics, menu. From this menu, you will be able to access your vehicle’s diagnostic system.
4. Scan for Trouble Codes
Select the option to scan for trouble codes. The scanner will communicate with your vehicle’s onboard computer and retrieve any stored trouble codes, and display them on the screen.
5. View Trouble Codes
Once the scanner completes its scan process, it will display the trouble codes retrieved from your vehicle’s system. Look for any codes related to the crankshaft position sensor. These codes usually begin with the letter “P,” followed by four digits.
6. Clear Trouble Code
To clear the trouble codes, select the Reset option. The scanner will send a command to the vehicle’s onboard computer to erase the stored codes. Within no time, all fault codes stored in your vehicle’s onboard computer system will be cleared.
7. Verify Code Clearance
After the scanner tool has reset a stored trouble code, the scanner will usually display a confirmation message. Make sure the crankshaft position sensor code is no longer present.
8. Turn Off Ignition & Disconnect Scanner Tool
Turn off your vehicle’s ignition and disconnect the scanner from the diagnostic port. After that, start the engine and test drive the vehicle.
If your vehicle has a fault with the crankshaft position sensor or the wiring is damaged, the trouble code will re-display after a brief period of time. In this case, you will need to correct the wiring and replace the CPS.
How To Test Crankshaft Position Sensor?
You will have three methods to test the crankshaft position sensor, which you can choose according to your convenience and the proper tools available.
1. With Multimeter:
- Connect the multimeter: Set your multimeter to the proper voltage or frequency setting. Next, connect the positive lead of the multimeter to the signal wire at the crankshaft position sensor and the black lead of the multimeter to the engine block.
- Crank the engine: After this, with the help of a helper, crank the engine and watch the reading of the bellows. The sensor should generate an AC voltage signal or frequency pulses when the engine is cranked.
- Check the voltage or frequency: You should see an AC voltage reading or frequency value on the multimeter when the engine is cranked.
- Compare readings: If the multimeter reading and the reading given in the repair manual fall outside the specified range, it may indicate a faulty crankshaft position sensor.
2. With Test Lamp
- Disconnect the sensor wire: Disconnect the electrical connector from the crankshaft position sensor.
- Prepare the Test Lamp: Connect the positive wire of the test lamp to the positive terminal of the vehicle’s battery, and connect the negative wire to a good ground connection to test the test lamp. Make sure the test lamp is working properly.
- Connect the Test Lamp: Connect the positive lead of the test lamp to the signal wire of the crankshaft position sensor.
- Crank the engine: Ask a helper to crank the engine while you keep an eye on the test lamp.
- Inspect the test lamp: The lamp should flicker or glow when the engine is cranked during the test. The flickering of the test lamp indicates that the sensor is generating a signal.
- Compare Test: If the test lamp does not flicker or flash, or if it is constantly on or off, this indicates a crankshaft position sensor problem.
3. With Scanner Tool
- Connect the scanner tool: Connect the scanner tool to the OBD-II port of the vehicle.
- Power On The Scanner: Enable the scanner tool to establish communication with the vehicle’s onboard computer system and proceed based on the menus provided.
- Confirm Trouble Codes: Click the scanner tool “Read Fault Codes” to retrieve any trouble codes related to the crankshaft position sensor. Click on the “Reset” option when you get the fault code.
- Monitor Live Data: Access the Live Data section of the sensor via the Live Data section of the scanner tool. View parameters related to the crankshaft position sensor.
- Crank the Engine: Start the engine and monitor the live data on the scanner tool while the engine is cranked. Watch the reading for the crankshaft position sensor.
- Compare with Specifications: Live data reading from the scanner tool and comparison with the specified values If the readings differ by comparison, this indicates a problem with the crankshaft position sensor.
Q. How Much Does Crankshaft Position Sensor Replacement Cost?
The total replacement cost of the crankshaft position sensor can be anywhere from $100 to $300. The cost of the sensor can range from $85 to $140, and labor costs anywhere from $50 to $175 at a mechanical garage to replace the crankshaft position sensor and repair the fault.
Q. Can You Drive a Car Without a Crankshaft Position Sensor?
Older vehicles’ engines are able to function without any sensors. So you can start older technology engines without a crankshaft position sensor. But in modern engines, all the sensors play an important role in the operation of the engine. That’s why modern engines can’t start without a crankshaft sensor, and you can’t drive a car without it.
Banty is the owner of Autorepairszone.com & is also a vehicle mechanic by profession. We have almost 12 years of experience in the field of automotive repair, and we strive to provide you with accurate information about vehicle malfunctions and repairs based on our experience.