I think it's a temp switch for the gauge ? The dealer says its efi and temp gauge related. Is that right? U guys ten to know the truck better than anyone else. Thanks in advance

 

That looks like the gauge sensor, efi and cold start sensors are both two wire

 

What year/engine type do you have? That will help us identify it better.

 

Sorry it's a 87 22re with 5spd

 

After market temp gauge sensor, based on the location and solid stripe on the wire. Check for the factory temp gauge sensor, it should be located in the center of the lower intake manifold and will be a single wire also.

 

It's deaf not Anything aftermarket it's a factory sensor the pigtail is broken.

 

Also my factory temp gauge always goes to the same spot whether its hot or cold

 

My schematics show the same. For a 1994, I show the wire to the gauge temp sensor is yellow with a green stripe.

But the easiest way to tell is follow the diagnostic http://personal.utulsa.edu/~nathan-b.../6combinat.pdf

If hooking a test light to ground on that wire causes the temp gauge to deflect, then I'd say you've found it.

 

TSW, EFi Temp switch. Plug "W" in the EFi schematic, item # 35 in the layout diagrams. Blue-green wire. Can see the plug type in the picture I linked in your last thread.
http://s3.amazonaws.com/f01.justansw...051909_egr.jpg
You can barely make out the gauge sender in this pic also, blue/grey bit just below and between the Idle up and Cold start.

 

On my truck I have two there.

One is a temp sender that signals the A/C to turn off if the water temp gets too hot (part of the towing package)

The other is a fuel pressure up switch
There is a TSB on it somewhere but the new sensor has long been discontinued

The one in your picture is the latter if im not mistaken

 

Its factory. There are separate sensors for the EFI and the gauage.

 

Well this one does not control my gauge cause I replaced the pigtail and sensor and my temp gauge still goes to the same spot on the dash whether its hot or cold I'm not sure what it does it dosent run any different

 

This is the answer.

 

Well I would not have worried about fixing it had I known that. My temp gauge always goes to the same spot that's what I'm lookin to fix

 

There is 3 temp sensors oh my 86.
The on under the Throttle Body, this one on top of the thermostat housing and one more about half way back on the intake manifold.

 

Like i said it's the TSW signal to the computer. It's L-G(Blue-green) wire on the 3v, and G-B(Green-black) on the 22r. Same plug type on both.The A/C temp switch is a square plug like the temp gauge. These are both slightly to the rear of the TSW, middle of the lower intake just below the Cold start injector. You might have these swapped around.Water temp sender is Y-G(Yellow-green) wire, sensor has variable resistence.AC temp switch is G(Green) wire, sensor is open above 108 degrees.I had pictures but my computer is unhappy and I can't use java so no attachments.

 

Looks like someones been screwing around with the style sheets and it's eating user formatting again..

 

I agree this is the correct answer. If the AC is running and this guage finds the water tempature is too hot (too much of a load on the motor), this will tell the ECU to turn off the AC compressor until the water temp falls back into the accectable range. It does nothing more. It does not tell the guage anything, that falls to the guage port on the intake manifold between #2 and #3 cylinders. It does not tell the ECU what the water tempature is...

The only trucks this came on is ones that came from the factory with AC

 

Here is the pictures from the wiring book.



Also the A/C one is not part of the EFI harness, the A/C cowl harness follows along side the EFI harness and goes under the throttle body near the THW sensor wire. The TSW is part of the EFI harness and exits the loom under the plenum near the aft injector wires and gauge temp sender.