Mystery Plug

[SirFoxx]

Hello--

I am wrapping up my HO conversion (yes, she runs!). In the process of making sure I have everything plugged back in and all the vacuum lines ran correctly, I stumbled across this plug. Its a two wire, flat, single sided latch plug. Found it on the drivers side of the motor, though it could have been accidentally pulled over there. Colors are Black, Black / green or yellow? (cant tell). Any ideas what it goes to?

p.s. For those curious, I used an '86 gt cam, gt40 heads, 19lb explorer injectors, and a '90 mk vii computer to do the conversion.

[gadget73]

Looks like the AC compressor plug.

[87gtVIC]

I second the ac compressor plug.

[SirFoxx]

Sweet! it was the ac plug. not sure how the heck it made its way to the drivers side of the engine.

Time for some vacuum lines.

The red line coming off the fuel pressure regulator goes to manifold vacuum?
PCV goes to manifold?
Green goes to egr?
Faded red goes to smog pump?
Black goes...?

I know, shame on me for not keeping track lol.

[87gtVIC]

Under your intake manifold you have a vacuum tree with a bunch of ports on them right?

One of the small ports goes to your fuel pressure regulator with that red stiff line

the big goofy swan neck port goes to the firewall mounted vacuum plenum

your pcv valve should loop back into the upper plenum through another port on the underside of the plenum above the pside valve cover and then to the center of the upper plenum into another vacuum hard line.

charcoal canister I think gets a port near the center of the upper plenum.

Cannot comment on the rest as I dont have them any longer.

[gadget73]

red is manifold vacuum. That should feed to the EGR solenoid and the two smog pump solenoids.

Green goes from EVR (egr vac regulator) to EGR valve

white and black are to the smog pump valves. I don't recall which goes where though. It will be on the emissions label. The upper one next to the trans dipstick is the TAD, the lower one by the pump is the TAB.

If you don't have a smog pump, cap them. If you do have a smog pump, remove it and cap them

honestly if you do it right, you can get rid of all of that plastic crap. Run one line from manifold vacuum to the EVR. Run another line from the EVR to the EGR. Make sure you orient them correctly, I forget which port goes to which spot but red is the vacuum one. Mark the lines in some manner to ID them. Get rid of the vacuum pluming in and out of the smog pump crap entirely.

[SirFoxx]

Soooo about the smog pump. I was seriously considering removing it when I saw a line coming off of it that went to a 't' junction. One of the legs at the junction goes to my cruise control. If I remove the pump, will my cruise still work? Also, is there a shorter belt I can buy that can bypass the pump just by the routing of the belt?

[Tiggie]

Cruise will be happy. The smog pump is only an supplementary vacuum source. I got rid of my smog pump, and I have only had my cruise kick off once on a very long and steep interstate hill climb.

A belt exists to bypass smog and keep ac but I can’t vouch for the number.

[gadget73]

I've been running without a smog pump for a long time, cruise works fine. You can actually eliminate the T and just provide vacuum to the cruise servo only. Mine had a check valve after the tee, I simply re-located the check valve to act as a connector between the cruise line and the line coming off the vacuum tree. Make sure you put the arrow towards the vacuum tree or it won't work.

[Kodachrome Wolf]

I've been running without a smog pump for a long time, cruise works fine. You can actually eliminate the T and just provide vacuum to the cruise servo only. Mine had a check valve after the tee, I simply re-located the check valve to act as a connector between the cruise line and the line coming off the vacuum tree. Make sure you put the arrow towards the vacuum tree or it won't work.

The '87 was setup the same way after the T with that check valve. Sounds like I set up my hoses the same way you did with the smog pump removed.

As far as running a bypass belt, I'm presently using a K060563 (MasterPro & Gates use that number). You may also see it as 6K563. The break down however is you essentially need a belt that's six ribs and a bit over 56" long (Mine measures 56-7/8" long). That particular belt was right on the fringe of being too short, but it did slip under the tensioner with a little work. Just a thought since I have seen a shorter belt posted, which may have been just a 56" belt, but that would have been too short. I definitely needed the extra 7/8" to get it in place.

I will mention that the belt won't go into place and clear the smog pump, or at least from what I observed when I was setting it up on my car. Bare minimum the pulley to the smog pump would need to be removed so that the belt can go up to the A/C compressor and tensioner.

[87gtVIC]

If you remove the smog pump make up a sleeve for the lower mount of the large flat tensioner bracket. One may even be able to hack off a side of the smog pump to use its case as the sleeve in combination with the small spacer that will fall out. Easy way to determine how long of a sleeve you need is to just measure the smog pump and the spacer that fell out. That length is what you would need to fab up. Some have run without this sleeve bolted into the lower mount but I find it cannot hurt to have in place keeping all things nice a ridged on the tensioner bracket.

[gadget73]

yeah I've had problems with the edge of the belt wearing on mine, and I think its the lack of spacer causing it. Its been on my list of stuff to make. A piece of plumbing pipe big enough to pass the bolt and cut to the correct length is all you need, no special magic parts here.