Who can name the sensor with the green square around it and no wire connected to it. I have found a lot of photos online, but found many different explanations of what it is. Back story I swapped a 1990 2wd body on a 1989 4x4 both trucks were manual 5spd 3VZE. For simplicity of keeping all the fun SR5 stuff working I used the entire engine, cab, frame etc wiring harness from the 2wd. There were only 2 differences, first of course the lack of 4wd light, but also the wiring harness had no plug to go to the unknown sensor. Can anyone identify what this sensor is, and why a 89 has it and a 90 does not?
I labeled the ones I think I know.





Thanks,

Ian

 

Im going to guess thats a 3.0L V6 and not the 22RE 4 cylinder?

 

Oh! Yeah, my bad! Yes, 3VZE!

 

I'm still lookin! If you figure it out plz post. I've got one on mine, but its all 'parts scattered around the garage' at this point.

 

I am still looking as well. I will post back if I find out. Anyone else know the answer to this mystery?

 

I think thats the water Temp gauge .

 

Temp sensor for auto to overdrive.

 

Thanks for the input Punchy, but It won't be the temps sensor for an auto because the truck was a 5spd, and the harness had a plug that went to this sensor. The Vin decodes to a 5spd, and there is no neutral safety switch or evidence that the harness had been modified. I thought the same thing that a PO had possibly swapped from an auto to a 5spd, but all this shows that the original truck was a 5spd.

And cryptkeeper, the water temp sensor and switch are on the right side. Note this is a single wire sensor, so it must be a some form temperature switch to turn on/off a function.

keep the ideas coming!

 

You might check this out:

https://www.yotatech.com/forums/f116.../#post51604072

 

Thanks 22REC, I have read that thread and it doesn't answer he question unfortunately.

 

You're welcome, sorry it didn't have the info you needed. I'll keep looking and post back if I come up with something.

 

This doesn't make ANY sense to me (location?), but what about a knock sensor? It shares the same style pigtail plug in, which I wouldn't think another sensor would.

 

When I get a chance I will dig up the harness I removed from this engine and follow the wire back to the ecm and see if I can find out its fuction by the pin in the ecm.

 

I think I got it!

https://www.yotatech.com/forums/f116...60/index2.html

i believe pre 1990 there was an additional water temp gauge. It looks like it was for EFI, but conflicting info shows it was to cut out a/c if engine got too hot. Either way, I think since my 1990 wiring harness does not have a wire going to this sensor, I should be good to go. Sure would be nice to know for sure what this sensor does though!

Ian

 

Awesome! Well... if you "fill up" your current wiring harness and there is nothing else to plug in, call it a win! =D Once its running you can probably hook up a voltmeter and check the ohms of the sensor as the engine temp rises, might give a clue as to whether or not it truly is a temp sensor. Otherwise, glue one of those little drink umbrellas in it and make a nice conversation piece!