Also named crankshaft position sensor or CKS sensor, the crankshaft sensor is located close to the crankshaft and the flywheel. It relays information to the engine computer on the engine speed, i.e. on the rotational speed of the engine per minute. The engine speed impacts the gas consumption - depending on the rotational speed detected by the crankshaft sensor, the fuel injection will adapt. In addition, the crankshaft sensor determines the position of the crankshaft and its rotational speed.
The crankshaft sensor is an inductive sensor; it consists of a magnet with a coil around it. This sensor does not need to be electrically powered.
However, this type of sensor is seen less and less in modern cars and it tends to be replaced by hall effect sensors, which is more precise, but also more expensive. The way this sensor works is similar to the PMH sensor, but it needs to be electrically powered.
Many symptoms can indicate a bad crankshaft position sensor. A faulty sensor can cause the engine to stall suddenly when you’re driving at reduced speed, or prevent the engine to start. It can also make it difficult to start, as the amount of fuel needed won’t be injected at the right time.
This issue with injecting the right amount of fuel can also lead to acceleration problems while driving. When you try to speed up, the acceleration is uneven.
In order to know if you’re driving with a bad crankshaft sensor, several checks can be carried out. First, you can test the crankshaft position sensor by using a multimeter in order to measure the electric resistance of the crank sensor: The value needs to be between 300 and 900 Ω (Ohm). This testing method is only possible if the sensor is an inductive sensor. To test with a hall effect sensor, you should use an oscilloscope which will measure the electronic signal.
Another option is to test the crankshaft position sensor with a diagnosis equipment. Once the tool is connected, the mechanic will scan your car system and will be able to let you know if the crankshaft sensor needs to be changed, if a cleaning would be enough, or if the problem is coming from another component of your car.
Sometimes, cleaning the crankshaft position sensor can be enough to make it work correctly again. In order to clean a dirty crank sensor, you will need to disconnect and unmount it. Then, you can clean it by using a special cleaning product on a cloth. This could be enough to reestablish the connection.
However, if the cleaning of the crankshaft position sensor is not enough, it will be necessary to have it replaced. In order to get the crank sensor of your car changed, get quotes on autobutler.co.uk and compare our garage prices.
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