I have no idea??

[swilliams]

I am trying to figure out every thing I can on my 86 c10 any thing you have to say will be helpful. Thanks for your help.

[blazing816]

The second pic is just the vacuum line that goes to the first pic, but I am not positive what is for exactly (mine is not connected).
The last pic is your charcoal canister, it is an emission standard that is suppose to catch containments before letting them out in the air.

[Boone83K10]

Pic 1: this is the tip in vacuum switch. it is for ESC and it has to do with your timing. ESC = electronic spark control

Pic 2: vacuum line going to ESC.

Pic 3: this is the TCC. it controls converter lockup for the OD trans. It receives a vacuum signal then sends electrical signal to trans on whether to allow lockup or unlock when vacuum drops.

Pic 4: charcoal canister. I imagine it gets its signal from a TVS (thermal vacuum switch). that would be located on the intake manifold. they only open when they reach a certain temperature by way of coolant. then it opens allowing vacuum to travel to canister to purge fumes from gas tank. it also routes vacuum signal to other components-- for you that is the TCC. (lockup would only occur once the engine is warm and also allows trans to warm up)

edit: although it looks like someone took out the TVS in the thermostat housing. also, the missing vacuum line on the charcoal canister is the line that would come from the TVS, and provide vacuum to canister.

[swilliams]

Blazing816 and Boone83K10 thanks for the answers. On the charcoal canister the middle line is hooked to this will this provide vacuum.

[swilliams]

I have more... I read in other posts that this is a sensor for the ECM (which I don't have) Then on the other side of the block I have this any suggestions.

[Boone83K10]

Yes, that is ported vacuum. It only opens once the throttle is pressed which is good for the charcoal canister. The open line though on the canister? Hmmmm, check your vacuum diagram on the radiator support next to the hood latch. That will tell you what should go there. The second pic looks like a knock sensor. Are you sure you don't have the "ECM". Really what they mean is the ESC computer, that is what the knock sensor is signaling to. Do you have a distributor that has a wiring connector on the back near the firewall? That would be ESC. Third pic is the coolant temperature switch.

 

[swilliams]

Yes the dist has the wires out the back                                           is this the reason for the 5 pin module in dist?                                                                                                               If pic 3 is a coolant temperature switch do I need this

[Boone83K10]

Yes that is ESC with 5 pin module. What color is the wire in that pic?

 

[swilliams]

the last pic is a sending unit on the thermostat housing.

[Boone83K10]

The color of the wire is what interests me, a pic further up is the coolant temp wire, dark green.

 

[swilliams]

This wire has been spliced


It comes from the loom just below it in the pic looks yellow or pink

[Boone83K10]

that isn't spliced. that is a factory connection going to a non factory location. the last bit of wire is yellow. the first is pink or white, I am having trouble picturing what that is really for. the only yellow wires I see on my wiring diagram are on a California ECM diagram which does go to the coolant temp sensor, but there should be a black wire with it for a two prong connection.

is your truck running? if so, crank it up and get it warm. now unplug the wire running to the thermostat housing. did the temp gauge quit working? if so then somehow that is your temp switch. the other part of the thermostat housing looks like a "nailhead" temp sensor which is what my truck has in the driver side head with a dark green wire going to it.

if not, unplug the dk green wire that I said was the temp sensor wire. did the gauge quit working?

post what you find.

[swilliams]

the truck was bought new in Dallas in 86. It did come with smog system that has been removed. It did have the 2 prong connector it was cut and removed that is why I said the wire  was spliced. Its not running right now I am upgrading ignition and adding a 1" spacer to carb but I have in the past removed the wire to thermostat housing when running and gauge still worked. The other spot on thermostat housing had a plastic top that had 2 places for vacuum lines it broke when I was removing to put new thermostat, it was not connected to any thing. The nail head looking one I have is the first pic in post #4 the wire is black.



I have not tried to unhook this one while at temp to see if it works. I don't have any sending units in my heads.

[Boone83K10]

That is what my truck has right there. That connector for temperature. Ok, that wire on the thermostat is purely for the ECM. The computer needed to know what the temp was to compute timing. It has nothing to do with the gauge. If you are putting in an HEI, you can get rid of all that crap. You can get rid of all the wiring that is coming out the firewall right below the tip in switch as referred to earlier. Keep the connector in the previous post, that IS for the gauge. I have no idea what the other dk green wire is from the earliest picture, must be ESC.

[swilliams]

Thanks for all the help. I know I will have more questions later