Elec. Question.
I`m wondering if maybe disconnecting the oil temp sensor , and see if that makes a difference? Whatcha think Bill?
How ever Bill`s odds were correct! Did not help. So at least can rule that out. I went for drive and after a short dist. car misfired like before, Oil temp went to low, No codes, pulled with engine still running. So I checked all fuses in both locations, All seemed good. How ever 10 amp. fuse # 22 in floor, (body control module- ign. 3) was missing. So I put one in. Started car everything normal. except Coolant temp would bounce back and forth between like 185 and 195, kept that up for 5-10 minutes running in garage, Then I revved it a couple times to maybe 4 -4500 and gauge steadied out. car was running perfect the whole time. I`m thinking this has got to be something simple. I am not good with elec. stuff , But will go over grounds etc. again in next few days. I hope what happened this time might help with diagnosis. Thanks so much for any help!!! P. S. Every time after shutting eng. off with oil temp reading low, the next time starting few minutes later It will be reading correctly again.
How ever Bill`s odds were correct! Did not help. So at least can rule that out. I went for drive and after a short dist. car misfired like before, Oil temp went to low, No codes, pulled with engine still running. So I checked all fuses in both locations, All seemed good. How ever 10 amp. fuse # 22 in floor, (body control module- ign. 3) was missing. So I put one in. Started car everything normal. except Coolant temp would bounce back and forth between like 185 and 195, kept that up for 5-10 minutes running in garage, Then I revved it a couple times to maybe 4 -4500 and gauge steadied out. car was running perfect the whole time. I`m thinking this has got to be something simple. I am not good with elec. stuff , But will go over grounds etc. again in next few days. I hope what happened this time might help with diagnosis. Thanks so much for any help!!! P. S. Every time after shutting eng. off with oil temp reading low, the next time starting few minutes later It will be reading correctly again.

I had faith the ignition switch would do it.So ECM, PCM or some stupid wire somewhere is causing all this grief?
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Anyway, got it all back together, Started, everything normal got about 1/2 block and misfired and oil temp went to low. Got back changed out oil sensor with the one I had changed out with the coolant one Sun. Which is a new Duralast. Started up , and coolant normal, bur oil temp not coming up read around 75-80 deg. Coolant was normal around 186deg. So I had read online that if you disconnect the sensor, and it goes to LOW, it is a bad sensor. So, I did that and sure enough it went to LOW on the DIC. Started car, ran normal with oil temp LOW. So I`m thinking the one I put in was the one that would not come up to normal temp in the coolant position before. So, I am thinking to try one more new oil temp sensor. Just one question. if there is a prob. somewhere in wiring or PCM that could possibly blow these sensors? Thank you! D.
Anyway, got it all back together, Started, everything normal got about 1/2 block and misfired and oil temp went to low. Got back changed out oil sensor with the one I had changed out with the coolant one Sun. Which is a new Duralast. Started up , and coolant normal, bur oil temp not coming up read around 75-80 deg. Coolant was normal around 186deg. So I had read online that if you disconnect the sensor, and it goes to LOW, it is a bad sensor. So, I did that and sure enough it went to LOW on the DIC. Started car, ran normal with oil temp LOW. So I`m thinking the one I put in was the one that would not come up to normal temp in the coolant position before. So, I am thinking to try one more new oil temp sensor. Just one question. if there is a prob. somewhere in wiring or PCM that could possibly blow these sensors? Thank you! D. 
C 5 dash while running, and it was doing the EXACT same thing as mine is. I think it turned out to be the PCM. As I recall, he had done all the same things as me (grounds etc.) Thoughts? Thanks, D.





Its SUPPOSE to be 5 VDC .
IF,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, The wires are SHORTED to a 12 VDC source, SURE, it could damage the new sensor. IF,,,,,, Its 5 VDC, then NO, the reff voltage usually cant or shouldnt damage the sensor.
WHERE CAN THAT DAMAGE HAPPEN?? We already discussed that. The wire harness on the drivers side of the manifod where it runs down to the back of the engine SEEN it happen a DOZEN TIMES!!!
Untape the harness and inspect the wire for chaffing.
You really sould use a meter and read the sensor in COLD and HOT water and see if it has the correct resistance and resistance sweep from HOT to cold and cold to hot.
Last edited by Bill Curlee; Mar 12, 2018 at 09:37 PM.
Its SUPPOSE to be 5 VDC .
IF,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, The wires are SHORTED to a 12 VDC source, SURE, it could damage the new sensor. IF,,,,,, Its 5 VDC, then NO, the reff voltage usually cant or shouldnt damage the sensor.
WHERE CAN THAT DAMAGE HAPPEN?? We already discussed that. The wire harness on the drivers side of the manifod where it runs down to the back of the engine SEEN it happen a DOZEN TIMES!!!
Untape the harness and inspect the wire for chaffing.
You really sould use a meter and read the sensor in COLD and HOT water and see if it has the correct resistance and resistance sweep from HOT to cold and cold to hot.





I have seen other harnesses have wire insulation issues for no reasons at all and if it were ME, I just would untape the harness and inspect the wires.
I have seen other harnesses have wire insulation issues for no reasons at all and if it were ME, I just would untape the harness and inspect the wires.






Hmmmmmmmmmm,,,,,,,,, There isnt a GROUND for that circuit (persay)
There is a 5 VDC REFERENCE WIRE and a (LOW REFERENCE ) signal wire. That sensor does NOT connect to ANY GROUND! PERIOD!
If I had to GUESS (I guess pretty good) I woud say that some wires are bare "SOMEWHERE" from the connector to the PCM.
SO,,,,,,, BROTHER,,,, Start at the connector and start UN-TAPEING the harness. You can get the vinal tape at any electrical supply house (HOME DEPOT) and easily retape the harness.
GET HOT!!



