Re: Engine Speed Sensor
Reply #10 –
The sensor part shorts out inside the potting material. Oil gets in the plastic. There are two sensors in the unit.
Both will short internally finally.
If they are bad you may be able to hear the engine misfiring at idle. Erratic pulses.
The replacement unit is solid metal on the end. No potting.
The ism added a crank position sensor to the cam sensor for backup.
If both of your sensors fail it flat bed time. Sounds like one is out already