Why Crankshaft Position Sensors Fail

The crankshaft position sensor is a precision instrument, so it needs to be running in tip-top shape to give an accurate reading. Without accurate readings from the crankshaft sensor, the engine may exhibit all sorts of different problems. We're going to walk you through a few causes of crankshaft position sensor failure before moving on to the signs that suggest your crankshaft sensor may have failed.

Wheel and Pin Damage

You may remember from our description of how the crankshaft position sensor works, that the sensor measures the magnetic pulses created by a toothed wheel or a series of pins. If any of the wheel's teeth, or the pins, are broken, snapped off, or worn down, then that will disrupt the pattern of the pulses. That means the crankshaft sensor will essentially be "confused" because it is receiving a flawed impression of the crankshaft's speed.

Magnetic Problems

The magnet, although necessary for the sensor, can cause problems. The magnet can attract metal shavings created in the engine by friction. If the shavings stick to the sensor or the wheel, they will throw off the sensor's measurements. They can also start to bridge between the sensor and the wheel. The sensor is designed to measure the movements of the wheel at a certain distance so the bridging, by bringing them closer together, throws the measurements off.

Circuitry and Wiring Problems

The internal circuitry and the wires that connect the sensor to power and to the car's engine control module (ECU) can also burn out. A short circuit or an open circuit in the sensor will make it fail to give a reading to the ECU. If the wires burn out, the sensor might not be receiving power for the electromagnet, or it might not be transmitting a signal to the ECU.

Are you experiencing issues with your vehicle and think it might be due to a bad or damaged crankshaft position sensor? There are a number of symptoms associated with a failed crankshaft position sensor that can help you in determining whether or not the CPS sensor is the problem. To learn more, check out this article about some of the most common symptoms of a bad crankshaft sensor from the experts at 1A Auto!

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