I purchased a 86 F150 last week and have been trying to get the coolant temperature gauge to read. I am convinced that this truck used to be fuel injected but was converted to carbureted. It has a 302 engine and a 4-Speed MT. so far I have only fixed the oil pressure gauge trying to find the wire for the temperature gauge. Attached are pictures of my current situation . So where should the coolant temp gauge sender be? the sensor in back with no wires? or the one in front with two wires going to it? super confused when I look online there is only 1 wire for gauge and you can ground to test it... Any input would be great

*I have already purchase new brake booster and master cylinder, need to order gastank and get my hands on a fuel pressure regulator.

 

Brown,
Welcome to the forum.


What you need to do is find a wiring diagram for your year truck.
Might look here 1986 EVTM - ???Gary's Garagemahal
and find what wire is for the temp gauge.


Now I do not know the EFI trucks & wiring but from what I have seen posted the computer has its own sensors/senders and the dash gauges its own.


That 2 plug at the front I think is for the computer for temp and someone did not install the one for the dash gauge.
With the wiring diagram you should be able to find the color wire for the dash gauge. Once found find a water port it can go in or remove the other one.


The one out back and this is only a guess but could it be a knock sensor?
Dave ----

 

My '86 302 has a red wire with white stripe such as yours in the first pic that wraps around and does a hook under the brake master cylinder. My temp sender is a single wire sender though (I though all '86's were, but I could definitely be wrong.

 

As was said, the multi-wire sensor is for the computer and has nothing to do with the dash gauge; Hampton tells us it's a red/white-stripe wire for the coolant temp sender, the oil pressure sender will be white/red-stripe if he's correct in what he tells us.

 

So is the sender in the side of the head?
I would have thought it would be in the intake but have seen some motors have it in the head.


Anyone know what that rear sender is? Oil or knock?
Dave ----

 

Awesome, I will try that red wire when I get home, I purchased the coolant temp sender last night should I put it in place of the two wire sensor in front of my carburetor on the drivers side? There is not a computer in this truck anymore

 

I would think if it was good for the computer it would be good for the dash gauge.
I just like to know where the sender was from the factory just so I know.
Dave ----

 

Most 5.0 efi was like the picture below. Of course someone swapped out the efi intake manifold on his, so he now has something different.

 

My temp sender is on the front drivers side of the manifold but it is an aftermarket manifold. I will take pictures when I get home (currently hunting). It worked for my dash gauge. I will also try to find the exact sender I bought though it won't be much use since you already bought one.

 

You also have a edelbrock manifold and your sender is in the same place as mine.

Correct Chris, it is white with a red stripe.

 

You guys Rock! confirmed that it is the red/white Wire, I should posted earlier!! Now I need to find my fuel gauge wires. and my Tachometer Wires. I have a aftermarket MSD ignition BTW

 

I also need to find the fuel gauge wires. Mine does not work at all. I do not have a tach so I cannot help you there either.

 

Looking back at your pic it looks like you will probably need more wire to reach the sender. What I like to do (you probably already know how to do this) is solder the wires together and put some electrically safe grease on the solder and then put shrink wrap on top of that. This depends on you having a solder gun though (a good investment if you have wires that were as messed up as mine). I can post pics on how to do that if you decide to take that route.

You will also need a boot or something to slip over the sender stud. When I get home I can find a link to the boot or you can do as I did and use a crimp on round terminal (I also used solder there). You can kinda see it in this pic from another one of my post.

 

I do have solder, shrink wrap wires etc. a link to that boot would be great

 

The tachometer wire is green/black in a DSII coil harness.
​​​​​​​I'm not sure who or how your MSD was wired up.