Signs & Symptoms of a Faulty Crankshaft Position Sensor

The crankshaft position sensor is an essential component of a vehicle’s engine management system. It plays a critical role in the proper functioning of the engine by providing the engine control unit (ECU) with information about the position of the crankshaft.

In this article, we will discuss the symptoms of a faulty crankshaft position sensor, how to start a car with a bad crankshaft position sensor, when to replace it, and some quick fixes for a faulty sensor.

What Is a Crankshaft Position Sensor?

The crankshaft position sensor is a type of rotary sensor that measures the position and speed of the crankshaft. It is usually located on the engine block, near the crankshaft pulley.

A crankshaft position sensor, also known as a crank position sensor or engine speed sensor, is a type of rotary sensor that measures the position and speed of the crankshaft. It is typically located on the engine block, near the crankshaft pulley.

The crankshaft position sensor sends signals to the engine control unit (ECU), which uses this information to determine the ignition timing and fuel injection timing. This helps to ensure that the engine is running smoothly and efficiently.

The crankshaft position sensor is an essential component of a vehicle’s engine management system. It plays a critical role in the proper functioning of the engine by providing the ECU with information about the position of the crankshaft.

There are two main types of crankshaft position sensors: inductive and magnetic.

  • Inductive sensors use a coil of wire to generate a voltage when it passes through a magnetic field.
  • Magnetic sensors use a magnet to generate a voltage when it passes through a coil of wire. Both types of sensors work by measuring the changes in voltage as the crankshaft rotates.

In modern vehicles, the crankshaft position sensor is often combined with the camshaft position sensor to create a single sensor that provides information about both the crankshaft and camshaft. This type of sensor is known as a cam/crank sensor.

Overall, the crankshaft position sensor is a crucial component of a vehicle’s engine management system. It helps to ensure that the engine is running smoothly and efficiently by providing the ECU with important information about the position and speed of the crankshaft.

Symptoms of a Faulty Crankshaft Sensor

There are several symptoms that may indicate a faulty crankshaft position sensor, including the following.

  • Difficulty starting the engine: If the crankshaft position sensor is not functioning properly, it may cause difficulty starting the engine.
  • Poorly running engine: A faulty crankshaft position sensor can also cause the engine to run poorly or misfire.
  • Check engine light illumination: The check engine light may illuminate if there is a problem with the crankshaft position sensor.
  • Stalling and shuddering: A faulty crankshaft position sensor can also cause the engine to stall or shudder, particularly when the vehicle is coming to a stop.

How to Start a Car With a Bad Crankshaft Sensor

If you are having difficulty starting your car due to a faulty crankshaft position sensor, there are a few steps you can take to try and start a car with a bad crankshaft position sensor.

Use starting fluid: Starting fluid, also known as ether, can be used to temporarily start a car with a faulty crankshaft position sensor. Simply spray a small amount into the air intake and try starting the car as you normally would.

Keep in mind that this is a temporary fix and the crankshaft position sensor should be replaced as soon as possible.

When to Replace Your Crankshaft Sensor

There are a few circumstances in which you should consider replacing your crankshaft position sensor.

  • When it’s faulty or failed: If the crankshaft position sensor is faulty or has failed, it should be replaced as soon as possible to ensure the proper functioning of the engine.
  • Every 80,000-100,000 miles: As a general rule of thumb, it is recommended to replace the crankshaft position sensor every 80,000-100,000 miles to ensure it is functioning properly.

Quick Fixes for a Faulty Crankshaft Position Sensor

If you are experiencing issues with your crankshaft position sensor, there are a few quick fixes you can try before replacing the sensor.

  • Reset the ECU by disconnecting the battery: In some cases, resetting the ECU by disconnecting the battery can fix issues with the crankshaft position sensor. Simply disconnect the battery and wait a few minutes before reconnecting it.
  • Clean the crankshaft position sensor with electrical cleaner: A dirty crankshaft position sensor can cause problems, so try cleaning it with electrical cleaner to see if that fixes the issue.
  • Check the wiring for any damage: If the wiring to the crankshaft position sensor is damaged, it can cause problems with the sensor. Be sure to check the wiring for any visible damage and repair or replace as needed.

Replacing the Crankshaft Sensor

If the quick fixes above do not solve the issue with the crankshaft position sensor, it may be necessary to replace the sensor. Replacing the crankshaft position sensor is a job that is best left to a professional mechanic.

The process involves removing the old sensor and installing the new one in its place. The cost of replacing the crankshaft position sensor will depend on the make and model of your vehicle, as well as your location.

On average, the cost to replace a crankshaft position sensor ranges from $120 to $400 (£95-310, €105-360).

Last Words

The crankshaft position sensor is an important component of a vehicle’s engine management system. If it is faulty or has failed, it can cause problems with the engine’s performance. If you are experiencing any of the symptoms of a faulty crankshaft position sensor, be sure to address the issue as soon as possible.

Whether you choose to try some quick fixes or opt to replace the sensor entirely, it is important to ensure that the crankshaft position sensor is functioning properly to avoid further issues with your vehicle.