1990 TC MAF conversion questions

[86VickyLX]

That and the engine runs generally cooler with it. Since the EGR lowers combustion chamber temperatures.

[Neal 97 250]

Thanks guys for your help. I will see about the EGR most likely will keep it on if it is easy enough to make work. I am sure it is.

But now new questions.
Well kinda the same ...

I removed the engine harness from the '95. Did not cut any wires, just unplugged everything. Not a bad job getting it out. Saved the ECM as well for whatever reason.

Now, I spent an hour or more stripping down the harness. Concentrating on getting the MAF wiring out but had to strip everything to do that. Now, There are two wires I have a question about The red wire and the black wire with the white tracer. They go thru the harness and connect with 4 or 5 other wires of the same color. They both have a lead that goes to the 3pack of relays. One relay in particular. It is the EEC relay.

Should I try to keep the relays part of the harness I am using or should I cut all ties and just leave the pins in the donor plug? I can take a pic and post tomorrow night if that helps.

The red wire has leads that go to just abut every plug on the harness. The black wire with white tracer goes to alot of them too.

Thanks,
Neal

[gadget73]

You don't need the relays. The red wire will splice to the ECM + wire somewhere. Thats what you're seeing at the relays. The black wire should be the ground, which also should splice into another existing ground. Mostly you just want the two data wires that go to pins on the ECM connector intact.

[Neal 97 250]

Yup. Thsat is what I figured after I had time to sit down and think on it some. The red and black wires go to the ECM and they splice off and go to other sensors/relays etc. All I need to retain is the pins on the ECM that go to the MAF and splice the red and black wires into the same wires on the existing vehicle. Then all other pins will come from the other pcm plug.

[86VickyLX]

The red and black wires go to the ECM

No, the red and black wires go to power and ground respectively.
http://fordfuelinjection.com/?p=6
Farthest right wire is the red wire, next to that is the black ground, and the other two are the pcm pins.

[Neal 97 250]

Thanks. They also go to the ECM and quite a few other places as well. They are spliced together with about 4-5 other red and black wires respectively.
You can see in that diagram you linked that the red wire goes to the LH and RH O2 sensors as well.

[86VickyLX]

Thanks. They also go to the ECM and quite a few other places as well. They are spliced together with about 4-5 other red and black wires respectively.
You can see in that diagram you linked that the red wire goes to the LH and RH O2 sensors as well.

Yes, power and ground, you don't necessarily need to use the power and ground from the computer. I'm mounting mine with a ground, and just a wire tapped into the ecm relay. Which is basically where those red wires come from anyway.

[gadget73]

the directions that come with the kits have you tap ECM + and - inside the connector just because its convenient. The + feed does go all over the place though. Just tap into it wherever is convenient for you to do so and it will work fine. I would probably tie the ground into one of the ground wires coming off the ECM just to be absolutely sure there is no goofy voltage differential across the body sheetmetal but thats just me being paranoid. Also, I've seen how these cars run with a bad ECM ground and its not pretty.

[Neal 97 250]

That's kind of where I figured I would be heading. I will probably strip enough back on the harness to tap in at the same spot as originally.

I just found out my engine came in yesterday. Chomping at the bit to go get it!
Just curious, aren't the newer Explorers distributorless or am I wrong?

[85crownHPP]

correct

[gadget73]

distributorless indeed. They have coil packs, probably the same ones the 4.6 cars use. Theres gonna be a funny looking sensor in the hole where the distributor belongs. Remove that and the distributor will fit.

[Neal 97 250]

Thanks guys. I was a bit worried about that but you guys haven't steered me wrong yet. So remove the sensor and instal the distributor? Good to know that even with no distributor the gear is still on the cam. Right???

BTW I got into contact with some programming Guru in Knoxville. He recommended I get a newer EEC from a mustang maybe 2000 or so model. He can take the EEC and change the cubic inch programming and maybe use the coil packs and MAF etc. Have you ever heard of this? Pros? Cons?
sounds like I would still run two brains for the cruise. Is that all I need the second EEC for or does it control more? Tranny, etc???

[gadget73]

yeah, the sensor has the gear. it drives the oil pump shaft just like the distributor does. Thats probably more why its there. A cam sensor isn't really that useful but having an oil pump that operates is kind of important.


Getting the wiring for an obd2 system installed will be a lot more involved. The computers are more flexible but its a lot of wiring. It would also have to be distributorless.


TO make cruise work with the 89-93 Mustang ecm, you need to keep the stock ecm for cruise, and use the Mustang brain for the engine. Transmission has no electronics, its just a dumb hydraulic unit.

[Neal 97 250]

Another question. I got the exploder engine today. Starting to strip it down now. Funny thing, it was made 1-3-2000 and in a 2001 explorer. It is the GT40p with the 4 bar heads. Now, it has the tan colored injectors. I thought it would have the orange ones didn't you guys?

Anyway I have a Mark VII ECM on the way. That will be just plug and play but the injectors are my concern. When I saw the tan injectors I thought I would just use the stock computer to get it fired andf running but if I am not mistaken the firing order will be screwed up. Am I correct?

So I will probably pull the yellow/orange injectors from the '95 TC and use the Mark VII computer and fire it up with that. Does that sound OK?

Then I can do the MAF conversion once I find an ECM. I have had a terrible time finding a mustang ECM from '89-'93. They are just not out there.

I have thought about using a newer model ECM from a mustang late '90's from a 4.6L. The reprogramming it for the 5.0 cid displacement. Then using the distributorless ignition. It will take some programming but I have someone who can do that for me in Knoxville. What do you think? Has anybody you know of ever done that or something similiar???

[86VickyLX]

Another question. I got the exploder engine today. Starting to strip it down now. Funny thing, it was made 1-3-2000 and in a 2001 explorer. It is the GT40p with the 4 bar heads. Now, it has the tan colored injectors. I thought it would have the orange ones didn't you guys?

Anyway I have a Mark VII ECM on the way. That will be just plug and play but the injectors are my concern. When I saw the tan injectors I thought I would just use the stock computer to get it fired andf running but if I am not mistaken the firing order will be screwed up. Am I correct?

So I will probably pull the yellow/orange injectors from the '95 TC and use the Mark VII computer and fire it up with that. Does that sound OK?

Then I can do the MAF conversion once I find an ECM. I have had a terrible time finding a mustang ECM from '89-'93. They are just not out there.

I have thought about using a newer model ECM from a mustang late '90's from a 4.6L. The reprogramming it for the 5.0 cid displacement. Then using the distributorless ignition. It will take some programming but I have someone who can do that for me in Knoxville. What do you think? Has anybody you know of ever done that or something similiar???

The injectors are fine as long as the electrical plugs are the same. The newer style could be used but the wiring harness would have to be modified for the injector connectors. They're still the 19# injectors though. You can run the Mark VII computer for the time being until you find the mass air computer. Just a heads up though, you'll more than likely experience the same stuff that my car, and GMGT's project '79 had problems with. Popping and backfiring.

It will run. But if it does start popping, here's what I recommend. Let the engine idle, it will go through a weird idle thing everytime you start the car up. It doesn't matter if it's hot or cold outside, the engine is warm or not. You'll know when it's happening, the engine will be running fine, then out of nowhere, it idles really poorly, it goes to the point of almost stalling, then the idle will come back up, and idle smoothly, no popping backfiring, or poor acceleration. You don't let it do this, it's gonna pop everytime you drive it after it's been running for a few minutes.
The only fixes I know of is a mass air conversion, or a carb conversion, since the engine ran well on both.