Fox T-Bird/Cougar Forums

since I am swapping in the 5.0 and going the EFI route I have come to the question of the fuel pressure relay.  since the TC FP is controlled by the IRCM module will I need to add a relay or is there a relay somewhere that I am unaware of?  looking for Tom or someone else that has done this swap to chime in.  Thanks

anyone?

Yeah,I've done that swap and I know what you're dealing with.I just can't remember off the top of my head what I did.It's a simple "pin swap" deal near the ECM.If you can hang on I can check my notes tomorrow and I'm sure I can tell you what to do.

well I have done some digging and I found some info in a post from Dominator "Fuel pump wiring harness from the computer to the rear form an 87-88 bird or cougar,with relay"  so I guess I am on the hunt again for some more wiring. :(  this is whats gonna hold me up, there are no fox cars in any of the junk yards here.

I should have asked first,what are you swaping in? a 5.0H.O.? The reason I remembered it being simple(for me) is because I bought an entire 93 Mustang and used the engine harness etc.I just had to get the T-Bird wiring to "talk" to the Mustang ECM.I have the'88 T-Bird elec.-vac.manual from Helm if I can help you.Let me know what you're doing.

5.0 mass air into an 88 turbo coupe.  I have the HO intake, shorty headers, edelbrock cam, and a stock 85 302.  not really sure if my combo will work or not I just need to get the wiring under control.

here is something to chew on.

I know exactly what you are after though.  Go to the fuel pump section and you will see how the EEC relay is in control of it. you have to flip to the next page to see the splice point that is fed by the eec relay.  the splice point comes back to the previous page and rolls through the coil side of the fuel pump relay.  That energizes the fuel pump relay and makes the contact close ,, from there the fuel pump kicks on.  THis really aint that hard to figure out,, just compare the 2.3 chassis wiring and see what you come up with.

 http://s47.photobucket.com/albums/f162/jcassity_bucket/

Looking at the 87 EVTM and hopping this is close enough to your situation:

The 5.0 has the fuel pump relay in the trunk and three wires running from under the right side of the dash to the trunk to control the relay.

The 2.3 Turbo has the Integrated Control Module up front and one wire running to the trunk for the fuel pump.

Installing a relay under the dash and using the one wire to the trunk for the pump looks like the way to go.

The 5.0 harness should have a 4 pin connector under the right side of the dash with red, yellow and tan/light green wires.
These are the three fuel pump relay wires.

In the area of the EEC module there should be a 4 pin connector with a pink/black wire in it.  This is the wire to the fuel pump.

Here is what you wind up with:
(http://mysite.verizon.net/vzetk5cc/sitebuildercontent/sitebuilderpictures/FuelPump87modified.JPG)

leme modify that a little to include what i mentioned earlier about you having to look at the next page.

softtouch
I like where you put the inertia switch, makes better sense there in my opinion.  having it on the coil side of the relay always made me wonder "what happens when the contacts are sticking.

I didn't move the inertia switch, I just changed the drawing to show where it is if you use the existing Turbo Coupe fuel pump wire.
(page 61)

well I am working on the repin of the grey and black connectors as per Dominator's write up and I have ended up with a few wires that were not listed and I am unsure of where they should go.  the wires that I have left over are:

Orange/yellow
White/Red

and then the ones listed by dominator

Black
Grey/White
Green/purple

any help here will be appreciated.

here is the link to Dominator's write up http://www.foxtbirdcougarforums.com/showthread.php?t=1218&highlight=TC+5.0+swap

red/white is the connection for the temp gage... Black is usually a ground...


Gonna take some digging to find the others...

I did same on my swap but the F/P relay is in the trunk same as original 5.0(I used a complete Bird 5.0 harness)... I just connected the power from the relay to the inertia switch same as orig to TC... I used the single TC F/P power wire to connect the the F/P monitor circuit on the MAF EEC...

did you mean white/red?  this is the wire that I am unsure of.  does this wire go back with the grey/black connectors? if so where?

Oops the white/red is the oil pressure gauge hookup...

I just looked at mine and I have no connections on the gray plug at all(it's just hanging the or/yel is in it)... Black plug is is mostly connected... I fabricated adapters from the 5.0 Bird body harness and the 2.3 engine harness and just plugged everything in... Been 10 years though(fall '99), I have a hard time remembering exactly what I did...

Can't seem to find my EVTM, was loaned to a buddy and I'm 99% sure he brought it back, puzzling why I can't put my hands on it...

I traced the wires on the back of my TC cluster to the oil guage and compared it to the plug and I came up with a white/pink for the oil sender wire so I connected the white/red to the white/pink.  someone correct me if I am wrong on this one. Thanks

ok another question, I have 2 orange/yellow wires and in the wiring schematic I have it says the orange/yellow is for the vehicle speed sensor, should I splice the two together or leave the one out? but then how do I know if I have the right wire?

If the two wires have continuity(ck with ohm meter), it will make no difference which you use or if they are spliced together...

Now that you mention speed sensor, I remember running wires for it from the shifter harness where it came up through the floor... That was my only real goof up... I'd added the connections for the SS to the EEC harness but didn't run those into the engine bay... Found out my goof when I'd already installed the harness and HVAC plenum(repl a seeping heater core), so those wires are run inside the dash(and why my gray plug has no connections at all)... Later on, I figured out I could have connected those wires to the ones from the original 2.3 EEC test connector... It's in the ride/ABS harness so is unused, I'm feeding gauges with those wires now... Guess you've figured out, I don't like poking random holes in my firewall LOL... Especially if there is any other choice...

BTW I found my EVTM, was where it was supposed to be, just on the wrong shelf...

I checked for continuity on the two wires and they seem to be tied together at some point as both of them lead to the same point in the eec connector.

when using a speed density HO computer will I need to do any repinning in the harness or will it be alright the way that it is?