i may have really messed up =( help please

[JayJ]

ok well i decided to do a 7mgte swap about 3 weeks ago and was doing loads of research on where everything fits and what parts i needed to make it work. well the one thing that i did not research or think about was the wiring harness.. because i was sending my harness to tweak'd preformance it didnt worry me because i was not going to have to work on the harness myself.. well i pulled the old 5m ecu and engine harness kind of mindlessly and sent it off to tweak.. well i was wiring up my wideband and boost gauge when i stopped and looked over at where i pulled the old ecu and saw some dangling plugs, i went to go grab my new 7m ecu just to see where everything matched up so i could mark it and realized my worst fear.. they didnt match up! =,( the body harness or whatever it is called behind the firewall that isnt part of the engine harness doesnt match up to the 7m ecu.. should i have sent tweak the other plug that was the body harness side of my old 5m ecu or do i just keep the old 5m ecu and plug that into the body half of the wiring harness and the engine part into my new 7m ecu? or do i really have to start cutting and splicing stuff to make the body plugs for my old 5m ecu match my new 7m? frankly im really scared here because i despise wiring and i dont want to mess anything up.. thanks in advance for any help

[4SFED]

I'm not sure I am following all this. But
You need the wiring harness and ecu that matches the engine you are running. Modified to connect to the car it's going into.
There are plenty of threads already here that tell you what you need to do so I don't think we need to do it all again here.
Start reading.

[buhay6]

^^^
+1

[ABQMK2]

Im not sure how tweak does it but the engine harness for the 7m will go to the 7m ecu. And tweak probably will make you a subharness to plug into the body plugs. I bet he will email you for an additional plug from the body. Im not sure how he is gonna run your ignitor set up. You also need an msd tach adapter unless he figures that out to.

Im interested in how tweak does this for u..let us know how it turns out..good luck with your swap.

[1982 Dragon]

Im interested in how tweak does this for u..let us know how it turns out..good luck with your swap.

Same here, and what they charge. Good luck

[cmdeshon]

these helped me a lot.

http://www.celicasupra.com/forums/sh...t=7mgte+wiring

http://web.archive.org/web/200808010...supras.org.nz/

http://www.supracharged.com/tech/wiring/index.shtml

[4SFED]

Jayj
You're going to have to have a talk with mr Tweaked. When you have to renegotiate the correct equipment that you need from him to manage your 7mgte and he wants to squeeze you just show him all this interest this thread is drawing on our forum and if he would come through for you ...

[JayJ]

wow thanks for all the responses guys. i will send him an email tonight to make sure i sent everything.. but to clear up what i ment a little bit more.. i have the 82 supra L-type, and the stock 5m ecu has 2 seprate plugs coming out of it, well the bigger of the two plugs goes out to the engine bay along with 2 other plugs from near the ecu that are not part of the ecu plugs but also go to outside the engine bay. well i pulled these 3 plugs out (one being dark orange directly being unplugged form the ecu) and 2 others that were around the ecu but not plugged directly in. well one of the dark orange pulgs that were plugged directly into the ecu stayed behind when i pulled the harness. it is wired up and around the defroster vents so i dont see what it goes to. but that one is what worries me, why did a plug that went directly into the ecu not come out with the engine harness? and as a secondary thing, why the hell didnt my mass air flow sensor plug not come out with the engine harnes? i would think that is a key part of the engine harness..? and yea i know about the tach adapter and everything i told him to wire that in for me. and he quoted me about 540 for the job plus whatever extra connectors he needs and the 40 for the tach.. thanks again guys..

[EwGoetsch]

I have a few 7mgte parts in Lakewood, hit me up

[CarFreek]

wow thanks for all the responses guys. i will send him an email tonight to make sure i sent everything.. but to clear up what i ment a little bit more.. i have the 82 supra L-type, and the stock 5m ecu has 2 seprate plugs coming out of it, well the bigger of the two plugs goes out to the engine bay along with 2 other plugs from near the ecu that are not part of the ecu plugs but also go to outside the engine bay. well i pulled these 3 plugs out (one being dark orange directly being unplugged form the ecu) and 2 others that were around the ecu but not plugged directly in. well one of the dark orange pulgs that were plugged directly into the ecu stayed behind when i pulled the harness. it is wired up and around the defroster vents so i dont see what it goes to. but that one is what worries me, why did a plug that went directly into the ecu not come out with the engine harness? and as a secondary thing, why the hell didnt my mass air flow sensor plug not come out with the engine harnes? i would think that is a key part of the engine harness..? and yea i know about the tach adapter and everything i told him to wire that in for me. and he quoted me about 540 for the job plus whatever extra connectors he needs and the 40 for the tach.. thanks again guys..

The 5m runs a few engine operating items thru the body, like the AFM and starter circuits. The 7m runs those thru the engine harness. Since the 7m never came in the MKII, the body harness plugs, and pinouts are going to be much different, also. What tweak should have asked for, if he understood what you were doing, was the 5m, and 7m ecus, plus several of the 7m body plugs. Then he supplys you with a "subharness" which adapts the 7ms harness to your 5m body harness. You, or someone, will have several splices to make into the cars body wiring, also.