I've removed the faulty sensor cleaned up everything (mine was rusty) reinstalled the sensor and all was good from then on. That worked 2 times a third time I needed to replace the sensor.

The sensors can be tested by placing the end close to an AC magnetic field and measuring the ac from the wires should be about 2 mV.

__________________
92 e300d2.5t
01 e320
05 cdi
85 chev c10