1996 Montero SR 3.5 dual cam. in last 300 miles the engine has gone through 3 crankshaft sensors. First time it threw a code for random misfiring, but on diagnosis my mechanic found the crankshaft sensor was broken from its mounting bolts and just dangling. Was sure he had resolved the problem. Replaced with a new crankshaft sensor- 5 hours of charged labor. In less than 150 miles engine died. Threw a code for a faulty crankshaft sensor. Thought maybe we just received a faulty sensor from the manufacturer. Replaced the sensor with another new sensor another 5 hours of labor, but mechanic did it under warranty. Car cranked and ran fine. Last night after about 80 miles on the new sensor the engine died again.
Need help or suggestions on what may be killing the sensors. Thinking maybe a short in the wiring between the sensor and the ECU, or possibly a bad ground. Any response would be appreciated.