my temp gauge hasn't worked since I built the truck, the water temp sender is hooked up, if I pull the connector off of it I can hear a relay go.. not sure. There's another wire, its green and yellow with a grey jacket and a grey spade connector on the end as far as my haynes manual tells me its a temp sensor wire. Where does it plug in? I seriously cant find anywhere for it to go? I haven't tested it with a volt meter yet I dont know what its for.

I dont even know if the section of wiring harness belongs to a 20R truck, I have another one in my parts shed that might be for the 20R I dont know if they are different or what but everything else works.

maybe just a bad water temp sender?

 

id say bad temp sender I just found out mine worked after I found the wire after I swaped in another engine... there are 2 wires on mine the yellow just plugs into the thermostat

 

some models have two sending units, one for the idiot light, and one for the temp. guage. Kev

 

I cant find where my temp sensor goes? The original owner said that sometimes the truck would get hot, so he took the temp sensor out and it was fine. Never overheated. I wanna put the thing back to make sure its fine, but have no idea where it goes on my 20r. Oh, and when I open the radiator cap, the coolant is RIGHT there. Is that normal?