What could cause this? Coolant temp sender wigging out

[Dr Tweak]

So, this 3SGTE swap is all but completed but there is one last issue that I'm dealing with. When I turn the key to on, the temp guage goes all the way up to the red. I thought maybe this was because the sensor was different, but they are the same between the 3SGTE and the '97 ST. I also took a temp sensor off a 4AGE and tapped a hole in the water housing and then installed it, but it does the exact same thing.

I know it's not a short in the wire because as soon as I unplug the connector the guage goes back down to cold.

Thoughts?

[brink]

You tested the sensor to see if it's bum?

[Dr Tweak]

Yeah, its good. Anyway it's fixed now. It turns out that the second wire coming from the guage that goes right to the ground was disconnected.

-Doc

[Bernight]

I'm having the same problem where dose the second wire ground at? Any info youmightbe able to give me would be great.

[Dr Tweak]

What year and model? And make sure you are plugged into the correct sensor.

-Doc

[Bernight]

It's a 94 helix pickup 22re. If I disconnect the wire it still goes to hot. I have the wirering diagrams from a chiltons but it's not much help.