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Cleaning up the Engine Bay Wiring and Vacuum lines


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For those of you who want to clean up your wire hiding a little more you can pull all the wires and vacuum lines inside and run them behind the dash.

Putting wires and Vacuum lines behind Dash
No matter how good you think your memory is when dealing with multiple wires and wires harnesses the 2 main things I feel that need to be done are mark each connector and what they’re connected to……. and take plenty of photos.
I couldn't find an easy way to pull the 2 large harnesses back inside other than by removing the dash and heater box so the first thing is to remove the seats and center console so that you have easier access to all the bolts and screws that hold the dash into place along with when you’re ready to pull the dash you have more working room.

I’ve read where people say you can pull the harness that is under the heater core back inside by not removing the heater box, but once you’ve removed the heater box you’ll see for yourself how tight the harness was to the heater box and just about impossible to pull back inside the cabin.
I have some diagrams that tell you where all the screws are placed that hold the dash to the metal frame work behind the dash cover, along with pics of how you disconnect the speedometer from the back if you’re interested?

Once you’ve removed the dash and heater box you need to go into the engine bay and push the large rubber grommets back inside that hold the 2 main harnesses onto the firewall.
With both harness back inside take a single edge razor blade and cut the large rubber grommet off the wire harnesses and then (the reason for doing this you’ll need all the length of wire that you can possibly get so that you don’t have to cut and splice any wires) you’ll need to peel back some if not all the old cloth tape and plastic shielding.

Separate the 10 pin connectors and the small wire harness that goes to the distributor along with the water temp sensor from the rest of the harness wiring. Now that you have those separate from the rest of the harness you'll need to cut a hole in the in the Trans Tunnel just big enough so that you can pass 1 of the 10 pin connectors at a time along with the harness that goes to the distributor and water temp sensor through the hole so that you can hook them up later once the engine is in. You can also put you’re your o2 harness in the trans tunnel if you want.

You’ll have plenty of wire left on the 10 pin connectors so there is no definite place you need to cut the hole in the Trans tunnel.
I went toward the top of the tunnel because there was more clearance, rather than toward the bell housing where there was less clearance.

Next untangle the BAP sensor wires from the main harness you’ll notice that there is no way to completely get the BAP sensors free of all the wires that go to the emission (TAD, TAB, EVR) these are the only wires I had to cut and splice when I pulled the wire harnesses back inside. Now take the wires that go to the BAP sensor along with the wire harness that ran along the passenger side inner fender in the engine bay and run them toward the passenger side kick panel right above the computer. You'll need to cut yourself a hole large enough above the computer so that you can pass the BAP sensor connector through this hole along with the wire harness that ran on the passenger side in the engine bay.

You’ll need to make some sort of rubber grommet around the hole once you have all the wires pulled through the hole on the passenger side so that the wires don’t get chaffed or cut later.
I used a small piece of 3/8” rubber hose that I had laying around that I split open with a single edge razor blade and then ran a bead of silicon inside the hose to that it would stay attached to the metal around the hole opening.
Make sure if you screw any components in the area of the computer that theses screws do not penetrate the thin metal cover of the computer… Check re-check and check again to make sure that nothing is going penetrated into the computer once it's secured to the inner fender.
For the Drivers side main wire harness cut a hole just below vacuum and wire harness that go to the cruise control servo between the outer and inner fender so that the wires and the wire harness can exit into the fender area. If you have eliminated your cruise control you could use that hole but might have to enlarge it some.

You’ll also need to use that same hole for the vacuum line from the large vacuum T back to the check valve for HVAC that is if you have moved the large vacuum T into the driver’s side fender.

You can separate EEC test port connectors from harness that is going into the driver’s side fender and just leave them inside the car and under the dash. It makes much easier with the EEC test connectors inside if and when you need to run a test for any codes.

This is now the time to re-wrap any wires or harnesses that you had to split open or took apart and make sure they are secure and not rubbing on any sharp metal.

Now that you’ve got the wires and harnesses rewrapped and poked through the new holes you made on the passenger and drivers side you need to attach them to the connectors and wire that you hid in the fender that I originally suggested in my write-up I had on wire hiding 101.. http://www.foxbodymustangs.org/community/threads/wire-hiding-101.620/

Here are some pictures that show how I ran the wires and vacuum lines behind the dash .http://smg.photobucket.com/user/almoststock/library/Wires Behind the Dash?sort=6&page=1
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