A crank angle sensor detects the rotational speed (engine RPM) and position of the crankshaft. It sends this data to the vehicle computer. This is vital as the crankshaft is in the heart of the engine and everything rotates, is driven off or timed off the crankshaft. They are a hall effect sensor (Magnetic) or an optical sensor and need to be extremely reliable and accurate.
Popular Questions Asked
What happens when Crank Angle Sensor fails?
I liken this to a band's bass player. The bass player keeps the band in time with the music or in sync. If the band loses the bass player, the bands timing is off and the song sounds disjointed or just stops as no-one knows what to do next. Likewise in the engine. If the crankshaft sensor fails everything just stops as you lose ignition timing. This means the fuel injection doesn't know when to squirt fuel and the spark plugs don't know when to ignite the fuel.
What are the symptoms of a failed Crankshaft Position Sensor?
Complete failure while the engine is off, then the vehicle will not start and the check engine light will be on. Complete failure while the engine is running would be catastrophic and could cause major damage. Most likely you will start to get warning signs of a failing sensor before it dies. The worst part is the symptoms can be caused by other components or it could be a combination of errors.
A scan tool that interrogates the computer is good for interpreting errors that sensors can generate and can point you in the right direction. Some symptoms can be:
Reduced fuel mileage and the check engine light on
Engine misfires, erratic acceleration or flat spots while accelerating
Rough idling, stalling or trouble starting
Will a car start without a Crank Angle Sensor?
No, the engine won't/can't run without a working Crank Sensor.