crankshaft sensor

[jerryt]

I have just installed my third crankshaft sensor since May of this year. The first 2 were installed by repair shops because I was on camping trips too far from home. This time I did it at home. My question is what can cause these sensors to fail? I do have a code for a bad knock sensor on #1 bank.

 

[Fast69Mopar]

I have just installed my third crankshaft sensor since May of this year. The first 2 were installed by repair shops because I was on camping trips too far from home. This time I did it at home. My question is what can cause these sensors to fail? I do have a code for a bad knock sensor on #1 bank.

Were you replacing the crank sensors because of ''No-Start" issues or because of check engine lights?

 

[jerryt]

Because it acted just like it did the last 2 times and the light on the dash in the lower right corner was flashing like it was before. I am thinking maybe the faulty knock sensor may have something to do with it. The first 2 times it went out I was pulling my camper, but managed to get to the camp ground and the it wouldn't start so I had to have it towed to a shop. This time I had brought the camper home and it acted up as I was leaving my driveway so I turned around and made it into my garage. Easy to fix myself at home.

 

[Fast69Mopar]

Because it acted just like it did the last 2 times and the light on the dash in the lower right corner was flashing like it was before. I am thinking maybe the faulty knock sensor may have something to do with it. The first 2 times it went out I was pulling my camper, but managed to get to the camp ground and the it wouldn't start so I had to have it towed to a shop. This time I had brought the camper home and it acted up as I was leaving my driveway so I turned around and made it into my garage. Easy to fix myself at home.

Which lamp was flashing in the lower right hand corner of the instrument cluster? Was it the ETC throttle lamp with the lightning bolt?

Also, the knock sensors, which there are two of them, one on each side of the motor, won't have any effect on the crank sensor.

The role the knock sensors play has to do with combustion detonation or spark knock which can occur with a poor quality fuel or high cylinder temps to name a few.

 

[Redtruck-VA]

I believe the knock sensor and crank sensor share the same 5v sensor source. The sensors also have their own isolated ground (reduced noise). I would check my wiring and connectors for damage. Knock sensor have a specific torque for it's mounting bolt. Just a side note for consideration I have crossed my sensor grounds with chassis ground years ago. In addition to a ground wire from the pcm to head to TB to chassis without issues.

 

[jerryt]

It was the ETC light that was flashing. I found a broken wire in the knock sensor harness. I read that engine vibration could cause crank sensor problems, so I thought maybe an engine knock could be the cause. I also don't remember torquing the knock sensor bolt when I replaced it about a year ago. Do you happen to know the specs on that?

 

[Redtruck-VA]

The torque spec for the 5.7L sensors are 20 Nm, or 15 ft-lbs, or 176 in-lbs.

 

[jerryt]

Thank you Redtruck.