Big Blue's Transformation

[Gary Lewis]

Here is mine, keeping in mind that I pretty much used the stock EEC location. This is looking forward, so left and right are as it goes into the truck.

Thanks, Bill. If I were to take a pic of my all-up harnii it would look very close to that.

As you know, I already have the harness across the radiator support. And I really, REALLY don't want to take that apart to add the oxygen sensor wiring. I also have to remember that I have the wide-band to wire. And that the wiring comes through the firewall.

So I'm more likely to run the oxygen sensor wiring across the firewall and drop down on either side to the exhausts. But that is going to require some protection.

[85lebaront2]

Thanks, Bill. If I were to take a pic of my all-up harnii it would look very close to that.

As you know, I already have the harness across the radiator support. And I really, REALLY don't want to take that apart to add the oxygen sensor wiring. I also have to remember that I have the wide-band to wire. And that the wiring comes through the firewall.

So I'm more likely to run the oxygen sensor wiring across the firewall and drop down on either side to the exhausts. But that is going to require some protection.

Gary, a couple of items, first being the ignition wiring. On the 1990 truck one did you notice the shielding (foil wrap) on the signal wires from the engine and partially to the EEC location? On the Ranger stub, same thing except it is a braided shield like coax uses over the same three wires.

On the 1990 F250, the three wires at the engine plug and of the shield are SPOUT, PIP and shield ground. I do not remember how the shielding went on the 1996 harness, other than the SPOUT, PIP and shield ground are in C101.

Since Big Blue never had a TFI module, other than having enough air flow for the heat sink, the only other consideration is access to the SPOUT circuit connector. On the Taurus the TFI module head sink is inside the cowl attached from the back side. You could use this location as I have a Taurus module heat sink which would allow placement near the EEC box and wiring but in a location away from the header heat (on the Taurus it was over top of the HVAC system and removed from inside the car). The only piece of the puzzle still searching for a convenient location would be the SPOUT connector.

[Gary Lewis]

Gary, a couple of items, first being the ignition wiring. On the 1990 truck one did you notice the shielding (foil wrap) on the signal wires from the engine and partially to the EEC location? On the Ranger stub, same thing except it is a braided shield like coax uses over the same three wires.

On the 1990 F250, the three wires at the engine plug and of the shield are SPOUT, PIP and shield ground. I do not remember how the shielding went on the 1996 harness, other than the SPOUT, PIP and shield ground are in C101.

Since Big Blue never had a TFI module, other than having enough air flow for the heat sink, the only other consideration is access to the SPOUT circuit connector. On the Taurus the TFI module head sink is inside the cowl attached from the back side. You could use this location as I have a Taurus module heat sink which would allow placement near the EEC box and wiring but in a location away from the header heat (on the Taurus it was over top of the HVAC system and removed from inside the car). The only piece of the puzzle still searching for a convenient location would be the SPOUT connector.

Morning, Bill.

On the ignition module location, I'd like to keep it under the hood, but thanks for the offer. I think below the speed control but with a heat shield will work well.

As for the SPOUT, I forgot to tell you that it is 12" the ECU's connector.

And concerning the foil, here's a before I pulled the foil and after on the '96 CA-spec 460 harness at the SPOUT & ECU. The foil came all the way to that point from C101.

[Gary Lewis]

Morning, Bill.

On the ignition module location, I'd like to keep it under the hood, but thanks for the offer. I think below the speed control but with a heat shield will work well.

As for the SPOUT, I forgot to tell you that it is 12" the ECU's connector.

And concerning the foil, here's a before I pulled the foil and after on the '96 CA-spec 460 harness at the SPOUT & ECU. The foil came all the way to that point from C101.

Well, I think I just had an epiphany.

Looking at the 1996 5.0L Canadian harness I discovered that it has the same connector with the same wire colors as my 460 CA-spec harness. BUT, it also has the ignition control harness with the right wire colors!

So, what I've been calling the ICM connector isn't. I don't know what it is, but I know what it isn't. Apparently the ICM connector was cut off of the CA harness before I got it.

So, I think I'll pull the ICM connector off of Huck's harness and graft it into the CA-spec harness.

[Gary Lewis]

Well, I think I just had an epiphany.

Looking at the 1996 5.0L Canadian harness I discovered that it has the same connector with the same wire colors as my 460 CA-spec harness. BUT, it also has the ignition control harness with the right wire colors!

So, what I've been calling the ICM connector isn't. I don't know what it is, but I know what it isn't. Apparently the ICM connector was cut off of the CA harness before I got it.

So, I think I'll pull the ICM connector off of Huck's harness and graft it into the CA-spec harness.

And, here 'tis. I pulled the terminals out of C101 on Huck's harness so they'll go into C101 on the 96 460 harness. And the R/LG wire will go back to S148 near the PDB.

However, I cut the wires at the PCM as I'll have to extend them anyway to get to the PCM under the dash. And, I'll put a shield on the GY/O and O/R wires, just like Ford did.

[Gary Lewis]

And, here 'tis. I pulled the terminals out of C101 on Huck's harness so they'll go into C101 on the 96 460 harness. And the R/LG wire will go back to S148 near the PDB.

However, I cut the wires at the PCM as I'll have to extend them anyway to get to the PCM under the dash. And, I'll put a shield on the GY/O and O/R wires, just like Ford did.

Moving right along, here's the ICM connector integrated into the harness. The pins have been swapped out in C101 and the R/LG wire is soldered to the R/LG wire coming from S148.

[85lebaront2]

Moving right along, here's the ICM connector integrated into the harness. The pins have been swapped out in C101 and the R/LG wire is soldered to the R/LG wire coming from S148.

Looks like you've got your rats, err ducks in a row on that! Don't forget O2 sensor numbering convention, HO2S 11 is right side, HO2S 21 is left side, HO2S 12 is turned off.

[Gary Lewis]

Looks like you've got your rats, err ducks in a row on that! Don't forget O2 sensor numbering convention, HO2S 11 is right side, HO2S 21 is left side, HO2S 12 is turned off.

Thanks, Bill. The HEGO numbering bewilders me, but I think I have it.

But, I just found a minor problem and need to re-open the discussion on switched power. I'll attach the pages from the '96 EVTM at the bottom of the post, but Page 27-1 shows that R/LG wire coming into the PDB as only pulling in the PCM relay. However, I've been wondering why that wire is a #10, so did a bit more looking today and found Page 13-5, which says that wire also powers the ignition control module, radio capacitor, ignition coil, and distributor.

Obviously running that through the resistor isn't "on". (Pun intended.) So let's re-open the previous discussion. You said:

R/LG under hood is one item, what else does it or the W/LB-H power? The later ignition switches I believe have a start and run combined feed. Looking at 1990 it does, at the ignition switch plug wiring. Just splice the two wires together in the harness under the dash, that's what Ford did as the 1990 ignition switch appears very similar to the 1985/86 one.

But why not just plug into C321 and pick up that W/LB-H wire? I want to use the connectors that are already there. So if I'm picking it up in one connector it doesn't look like splicing the two wires together helps since I can only pick one of them.

Or, if I want to join the two wires why not use both C321 & C325 and join them in my EFI harness instead of changing the '85 wiring? That would spread the load across two connections. And, Ford used fairly small wire on the downstream part of those connectors, so it would seem good to use both of them.

Here's the '96 page that led me to believe that the R/LG wire only pulls in the PCM relay:

And here's the one that disabused me of that understanding:

 

[85lebaront2]

Thanks, Bill. The HEGO numbering bewilders me, but I think I have it.

But, I just found a minor problem and need to re-open the discussion on switched power. I'll attach the pages from the '96 EVTM at the bottom of the post, but Page 27-1 shows that R/LG wire coming into the PDB as only pulling in the PCM relay. However, I've been wondering why that wire is a #10, so did a bit more looking today and found Page 13-5, which says that wire also powers the ignition control module, radio capacitor, ignition coil, and distributor.

Obviously running that through the resistor isn't "on". (Pun intended.) So let's re-open the previous discussion. You said:

R/LG under hood is one item, what else does it or the W/LB-H power? The later ignition switches I believe have a start and run combined feed. Looking at 1990 it does, at the ignition switch plug wiring. Just splice the two wires together in the harness under the dash, that's what Ford did as the 1990 ignition switch appears very similar to the 1985/86 one.

But why not just plug into C321 and pick up that W/LB-H wire? I want to use the connectors that are already there. So if I'm picking it up in one connector it doesn't look like splicing the two wires together helps since I can only pick one of them.

Or, if I want to join the two wires why not use both C321 & C325 and join them in my EFI harness instead of changing the '85 wiring? That would spread the load across two connections. And, Ford used fairly small wire on the downstream part of those connectors, so it would seem good to use both of them.

Here's the '96 page that led me to believe that the R/LG wire only pulls in the PCM relay:

And here's the one that disabused me of that understanding:

I suggested using C321 and C325 as Ford did on the EEC systems in 1985/86. They built the left side of the wiring harness to be pretty well universal for gas engines. What was plugged in to C321 and C325 depended on type of system, EEC, EFI or DS-II.

When I looked at the 1990 system, the ignition switch harness has the two power sources cranking and running connected at or near the ignition switch, almost like Ford had a supply of them that needed to be depleted. Motorcraft shows a different number for 1980-86 and 1987-91, they sure look the same though.

O2 sensor numbering is two digits, first is bank number, bank one being the bank #1 cylinder is on, second digit is location in the exhaust line, #x1 being first sensor, always pre-cat as it is the mixture control for that bank or the whole engine on an in-line. Sensor #x2 is 2nd sensor for the bank or system and is usually post-cat and measures the cat efficiency. One other sensor of note on these, a temperature sensor to detect a cat overheat condition.

[Gary Lewis]

I suggested using C321 and C325 as Ford did on the EEC systems in 1985/86. They built the left side of the wiring harness to be pretty well universal for gas engines. What was plugged in to C321 and C325 depended on type of system, EEC, EFI or DS-II.

When I looked at the 1990 system, the ignition switch harness has the two power sources cranking and running connected at or near the ignition switch, almost like Ford had a supply of them that needed to be depleted. Motorcraft shows a different number for 1980-86 and 1987-91, they sure look the same though.

O2 sensor numbering is two digits, first is bank number, bank one being the bank #1 cylinder is on, second digit is location in the exhaust line, #x1 being first sensor, always pre-cat as it is the mixture control for that bank or the whole engine on an in-line. Sensor #x2 is 2nd sensor for the bank or system and is usually post-cat and measures the cat efficiency. One other sensor of note on these, a temperature sensor to detect a cat overheat condition.

Ok, a combo of C321 and C325 it is. I'll bridge them in my harness. That way if anyone if using this approach it can all be done in the EFI harness.

As for the numbering scheme, that makes sense. And it helps.

Thanks.