Joes:
how can i test to see if it is a mvr sensor?
If it's an MVR sensor then the sensor will be slightly magnetic and it will produce a weak alternating electrical signal when ferrous material is moved towards and away from it. The magnitude of the signal is determined by the speed of the movement. This type of sensor is commonly used to detect the position of an iron/steel toothed wheel.
Hall effect sensors are not magnetic but require a magnet in the part being sensed.