What Happens When the Crankshaft Sensor Goes Bad

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Your vehicle is equipped with multiple sensors that constantly monitor different engine functions. One of these sensors is the crankshaft sensor. The crankshaft sensor monitors the position and speed of the crankshaft and relays this information to the engine control unit (ECU).

A bad crankshaft sensor will result in a failure of the ignition and fuel injection systems. This will cause the engine to stall or not start at all. In some cases, it may also cause the engine to run erratically.

If you suspect that your crankshaft sensor is going bad, it’s important to have it checked out by a professional as soon as possible. A failing crankshaft sensor can lead to serious engine damage if not repaired in a timely manner.

What Happens When the Crank Shaft Pressure Sensor Goes Bad?

Dorman 907-854 Engine Crankshaft Position Sensor Compatible with Select Ford / Lincoln / Mercury Models

The crankshaft sensor is one of the most important sensors in your vehicle. It relays information about the position and speed of the crankshaft to the engine control unit (ECU). This information is used by the ECU to control ignition timing and fuel injection.

If the crankshaft sensor goes bad, it can cause a number of problems. The most common problem is that the engine will stall. The engine may also run rough or misfire. In some cases, it may be difficult to start the engine.

A bad crankshaft sensor can also cause the check engine light to come on. If you have a check engine light and a code reader, you may be able to read a code that indicates the crankshaft sensor is bad.

If you think your crankshaft sensor may be going bad, it’s important to have it checked out by a mechanic as soon as possible. A bad crankshaft sensor can cause serious engine problems if it’s not fixed.

7 Symptoms of a Bad Crankshaft Position Sensor

Walker Products 235-1394 Crankshaft Position Sensor

The following are seven symptoms that may occur if the crankshaft position sensor is failing.

1. Excessive Engine Vibrations

As the crankshaft position sensor begins to fail, it will cause the engine to run excessively rough. This is usually the first symptom of the sensor going bad and happens because the sensor is not able to properly read the position of the crankshaft. This will cause the engine to run on fewer cylinders than it should, which will lead to increased vibrations.

2. Check Engine Light Turns On

One of the first warning signs that the crankshaft position sensor may be going bad is the check engine light turning on.

3. Hard to Start the Vehicle

If the crankshaft position sensor is failing, it can cause the engine to be hard to start. This is because the sensor is not able to correctly sense the position of the crankshaft and will not send the correct signal to the ignition system.

Also Read: Bad Fuel Pressure Regulator Cause No Start

4. Engine is Stalling

The engine stalling is a more serious symptom of a failing crankshaft position sensor. This can happen while the vehicle is idling or driving at low speeds.

5. Engine Misfires

Another symptom of a bad crankshaft position sensor is engine misfires. This happens because the sensor is not sending the correct signal to the ignition system, which causes the spark plugs to fire at the wrong time.

6. Reduced Engine Performance

A failing crankshaft position sensor can also lead to reduced engine performance. This is because the sensor is not able to correctly sense the position of the crankshaft and will not send the correct signal to the fuel injection system.

7. Reduced Fuel Economy

Last but not least, a failing crankshaft position sensor can also lead to reduced fuel economy. This is because the sensor is not able to correctly sense the position of the crankshaft and will not send the correct signal to the fuel injection system. As a result, the engine will run less efficiently and use more fuel.

What Causes a Crankshaft Position Sensor to Go Bad?

ACDelco Professional 213-4761 Engine Crankshaft Position Sensor

The following are the most common causes of a bad crankshaft position sensor:

1. Overheating Engine

Combustion engines generate a lot of heat. Consequently, the sensors that are used to monitor and regulate the engine’s performance are also subject to high temperatures. Crankshaft position sensors are no exception. Over time, the heat generated by the engine can cause the sensor to malfunction.

Also Read: Car Overheating When Idle

2. Circuitry Problems

More often than not, it’s not the sensor itself that has gone bad but rather the circuitry that is used to interpret the sensor’s signal. Over time, corrosion and other factors can cause the circuitry to break down, resulting in a false or inaccurate reading from the sensor. The harness that connects the sensor to the circuitry can also become loose or damaged, causing similar problems.

Crankshaft Position Sensor Function

It is one of the more important sensors in your car as it relays information about the position and rotational speed of the crankshaft to the engine control unit or ECU. The ECU uses this data to time the spark correctly so that the spark plugs fire at the right time and ensure that the fuel is injected into cylinders at the optimum time. This ensures that your engine runs smoothly and efficiently.

Crankshaft Position Sensor Location

To get to the crankshaft position sensor, you’ll need to remove the battery and battery tray. Once the battery is out of the way, you should be able to see the crankshaft position sensor mounted on the side of the engine block. It’s usually a black or metal-colored box with wires running to it. You can identify it by looking for the wires running to it from the engine control module.

Crankshaft Position Sensor Replacement Cost

This is a bit difficult to answer because it depends on the make and model of your car as well as the labor costs at your particular location. However, you can expect to pay anywhere from $200 to $400 for the sensor itself and another $100 or so for labor.

Also Read: How much does it Cost to Replace a Crankshaft Position Sensor

Conclusion

A failing crankshaft position sensor can cause a host of engine performance problems, so it’s important to be on the lookout for symptoms of a failing sensor. If you suspect that your crankshaft position sensor has gone bad, have it diagnosed by a professional technician as soon as possible. They will be able to tell you for sure and can also give you an estimate of the replacement cost.

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