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Shady302
06-16-2019, 04:05 PM
I'm hoping that some of the wiring gurus can help me on this and tell me that all hope is not lost.

To start, have a full dieted wiring harness minus injector harnesd that was made for me for my original harness from an 87 mustang.

I then purchased a mass-flo (now pro-m efi) set up from a forum member who was using a 94 wiring harness (and he gave me). I did not realize untill just now that the 94 harnesses would not match up, only learning that my harness seems to be an 87-91 harness.

I realized this after I have the whole rear harness and dash harness all installed only to go and connect the ECM harness to find out that they're totally different connections.

Question 1) Is there any way to just change the adapter to make this harness work with the 87-91 main OR do I have to have a whole new engine harness made to fit the mass-flo system with my current harness?

Question 2) My other concern is there is CCRM on the current
mass-flo harnesss, and a couple other boxes I'm not familiar with, whereas the dieted ecm harness from my 87-91 is missing a lot of these connections and wasn't sure if this is going to affect the mass-flo system.

My hope is to maybe use the 87-91 harness since it is setup for my harness and adapt the mass-flo connectors to that harness........as long as the other relays and boxes aren't needed.

Might be best if mustang medic (or anyone who diets expertly) and if Chris from mass-flo/pro-m efi chimes in too. Thanks.

Ray
06-16-2019, 04:22 PM
Get a hold of Mark (https://thefactoryfiveforum.com/member.php?10-Mark-Dougherty) I believe that he lives somewhat near you and has helped dozens of builders.

Ray

karlos
06-16-2019, 05:18 PM
Does your Pro-M EFI harness look like the graphic below? If so, I have the installations instructions and would be happy to make them available to you. Pretty straightforward, really. There are a small number of connections that need to be made between the Pro-M EFI harness and the main vehicle harness. The instructions spell things out pretty clearly.



https://thefactoryfiveforum.com/attachment.php?attachmentid=108977&d=1560723209

i.e.427
06-16-2019, 05:49 PM
Does your Pro-M EFI harness look like the graphic below? If so, I have the installations instructions and would be happy to make them available to you. Pretty straightforward, really. There are a small number of connections that need to be made between the Pro-M EFI harness and the main vehicle harness. The instructions spell things out pretty clearly.




Pretty sure he has a dieted Mustang harness and just a MAss-Flo from Chris.

I do have a couple 87-93 MAF stock meters if you need one. Let me know though PM and we'll see if we can set you up.

You could also see if you could splice this connector into your 87-93 Harness.

https://www.rockauto.com/en/moreinfo.php?pk=50307&cc=1134133&jsn=534

Shady302
06-16-2019, 06:44 PM
Does your Pro-M EFI harness look like the graphic below? If so, I have the installations instructions and would be happy to make them available to you. Pretty straightforward, really. There are a small number of connections that need to be made between the Pro-M EFI harness and the main vehicle harness. The instructions spell things out pretty clearly.
Karlos, I would love to see those instructions. It would definitely help me to understand how the mass flow system needs to be set up and what is critical on the setup. I would really appreciate that


Pretty sure he has a dieted Mustang harness and just a MAss-Flo from Chris.

I do have a couple 87-93 MAF stock meters if you need one. Let me know though PM and we'll see if we can set you up.

i.e.427, I probably do not need to have the MAF stock meters because I would like to get the mass flo to work.

And to clarify, I do have a dieted 87-91 harness which is ready for the A9L computer, and I also have the other separate harness that the other person gave me when I bought the mas flo system, which is a 94 harness and it came with a T4M0 computer but was completely setup for the mas flo system.

i.e.427
06-16-2019, 07:19 PM
Just so were clear. If you have a dieted 87-93 harness it is NOT the system pictured in Karlos' post. A dieted 94 harness is also not the pictured harness in his post. You are dealing with a factory Ford harness that has been dieted. Both of those factory Ford harnesses use a MAF meter, they are not however, the system from Mass-Flo (Pro-M). The Pro-M system uses an ECU specifically for their system and is not compatible with an A9L

You can also NOT use an A9L ECU with a 94 harness.

karlos
06-16-2019, 07:44 PM
Color me confused. As 427 says above, the Pro-M system uses a proprietary ECM and associated EFI harness. When it was stated that the system came from another forum member, I made the assumption that it was previously installed and up and running at some point, in which case the EFI harness would come with. Maybe a bad assumption on my part. Sent you a PM to which you can reply with your email address. I'll go ahead and send the instructions but may be moot.

If all you have is the Pro-M ECM then I believe you're gonna need the harness, too. $800 from Pro-M :eek:

Shady302
06-16-2019, 08:15 PM
Just so were clear. If you have a dieted 87-93 harness it is NOT the system pictured in Karlos' post. A dieted 94 harness is also not the pictured harness in his post. You are dealing with a factory Ford harness that has been dieted. Both of those factory Ford harnesses use a MAF meter, they are not however, the system from Mass-Flo (Pro-M). The Pro-M system uses an ECU specifically for their system and is not compatible with an A9L

You can also NOT use an A9L ECU with a 94 harness.

That's where this area might be a bit confusing. This is an older mass-flo unit. The computer does work for this setup because this must-have been when they actually used the original mustang computer to run it. They must have flashed it and reprogrammed it to work. This may have been the old way of doing it. I'll try to post a pic but of cpu. Btw, it's actually a T4MO computer. I just realized that now. I will edit my posts above.
And to be clear, this setup came out of a forum members running car. He used it for a few thousand miles.

GWL
06-16-2019, 09:14 PM
The old Pro-M units that used the A9L computer has a plugged in card. I've got one of his old computers with the plug card plugged in. I've talked to Chris at Pro-M and for my use he said I just had to unplug it. Right now it still has the card plugged in as I was keeping it for a spare computer and was going to just unplug the card when I needed it.

So, I have that card that I'll not be using. PM me if interested.

Maybe card is not the proper word but is, I guess, the 'chip'

George

Just puttering
06-17-2019, 11:46 AM
Im lost,
1. you have an 87 mass flow ford complete harness for the car. What changed the original that you needed it "flashed" to work? Or was it an 87 speed density system that got upgraded to mass flow? If still speed density, you will need a MAF and the connector (see I.E.427 post (thanks for the link, I need a new connector and now have the part number))
2. You got a 94 pro-m with the engine harness and a 94 ford complete harness with a t4mo ECM. Or you got a 94 pro-m that is made to mate to a 94 ford harness?

Get wiring diagrams for an 87 and 94 car. Figure out how to read them. With out this i would not move forward!!!

If needed get a 94-95 mustang connector for the ecm from a wrecking yard.

Be specific on what parts you have. even a picture or 2. and this should be fairly easy to set up.

Also, with the pro-m the t4mo and the a9l will not be used!