2000 Limited 5.0 L V8 Throws Code P0118

[Colin The Boss]

So my Black Explorer with the V8 keeps throwing the code P0118. The temperature sensor works as the dash gauge does move with the engine heating up. But the computer keeps saying the temperature is -40 when I plug in my OBD scanner. This issue causes the truck to idle at 2000 RPM randomly, and it can even do it while driving which makes it harder to stop the truck. Anyone understand why this might be happening or what might be causing it?

Thanks so much!

Colin The Boss
Student at ISU

 

[Dono]

There's two sensors. The one that raises the temp gauge is a different sensor.
The gauge sender has one wire. the coolant temp sensor has 2.

99 5.0 Temperature sensor location

how do i replace engine coolant temperature sensor?

 

[Colin The Boss]

There's two sensors. The one that raises the temp gauge is a different sensor.
The gauge sender has one wire. the coolant temp sensor has 2.

99 5.0 Temperature sensor location

how do i replace engine coolant temperature sensor?

Thank you so much. I feel so stupid. I have been looking at the temperature sender this whole time. I will replace the Coolant Sensor and see if that fixes the issue.

Thank you so very much for the help Dono!!

Colin The Boss
Student at ISU

 

[Dono]

Hey, no problem. Happy to help.
I find it bit odd that two different sensors are required.

 

[koda2000]

Hey, no problem. Happy to help.
I find it bit odd that two different sensors are required.

Well they do two different things for two different purposes. The one for the phony temp gauge, which has the needle sit in the approx center of the gauge as long as the coolant engine temp is within an acceptable range (maybe 167F-200F) where the temp sensor reports specific temp reading to the PCM, which is used to enter closed-loop mode for the O2 sensors. It's a bit like controlling the automatic choke on a carb'd engine.