A speed/timing sensor measures the rotation of a component to determine its physical rotational speed. When it is monitored, it can be used to decide the correct air/fuel mixture, the spark advance, and variable valve timing for your engine. The speed timing sensor is a magnetic coil that is fixed static to the engine block and reads the teeth on the crankshaft as it rotates. As the crankshaft spins during driving, an induction current is created around the magnetic coil. The crankshaft’s serrated edge obstructs this magnetic field and the result gets recorded. This measurement is reported to the engine control module to determine how engine performance settings will be altered. If the crankshaft speed/timing sensor isn’t reading properly or at all, the Check Engine light will come on and engine performance will be compromised.
Facts to Note:
There can be multiple speed/timing sensors in your vehicle as some designs monitor crankshaft speed while others monitor crankshaft and camshaft speeds.
How to Fix:
The engine trim cover is detached for access
The defective speed timing sensor is detached
The new speed timing sensor is fixed
The engine trim cover is reinstalled
The vehicle is road tested and speed timing sensor operation is checked
The speed timing sensor must operate correctly to obtain optimal vehicle performance. There is no service interval for the crankshaft speed/timing sensor. If your vehicle has related symptoms, have one of your expert mechanics diagnose the speed/timing sensor.
Common symptoms indicating you may need to change the Speed Timing Sensor:
Low coolant light comes is on
Lack of power
Check Engine light is on
Importance of this service:
The engine performance is reduced if the speed/timing sensor is reading an incorrect value. While the engine may still run, it will not run well and the problem should be rectified.