In desperate need of help with my 4v swap!

[4vCrush]

Originally Posted by na svt

nope, not enough adjustment. A canned tune will be better thana stock tune but not as good as a dyno tune.

Thanks man.. I guess I'll be visiting R.E.T. soon

[shame302]

Originally Posted by na svt

nope, not enough adjustment. A canned tune will be better thana stock tune but not as good as a dyno tune.

This. In fact, the hand held is useless as tits on a bull with out being pre-loaded with some sort of template already.

And leave the harness under your dash alone.

[4vCrush]

Originally Posted by shame302

This. In fact, the hand held is useless as tits on a bull with out being pre-loaded with some sort of template already.

And leave the harness under your dash alone.

Thanks.... so if i dyno tune my car will they fix my O/D being off.?? And the traction control that only stays on??

[shame302]

Well, If I'm keeping up right, you are now on your GT ECM, harness and have the car up and running?

Also, You kept your auto trans, correct? Honestly, without knowing why Traction control is stuck on, and your OD is stuck off, I'm going to say you have an issue that the tuner isn't going to be able to tune out. Something didn't go back together right when you swapped back to the factory GT harness. He could likely still delete/turn traction control permanently off for you though but that doesn't solve what's actually going on with it.

Somehow I missed that the car was an auto and the mach electronics were from a stick car. Pretty sure that was never going to work unless the stick car ECM has the auto transmission functions in them. I know you can go the other way though.

[4vCrush]

Originally Posted by shame302

Well, If I'm keeping up right, you are now on your GT ECM, harness and have the car up and running?

Also, You kept your auto trans, correct? Honestly, without knowing why Traction control is stuck on, and your OD is stuck off, I'm going to say you have an issue that the tuner isn't going to be able to tune out. Something didn't go back together right when you swapped back to the factory GT harness. He could likely still delete/turn traction control permanently off for you though but that doesn't solve what's actually going on with it.

Somehow I missed that the car was an auto and the mach electronics were from a stick car. Pretty sure that was never going to work unless the stick car ECM has the auto transmission functions in them. I know you can go the other way though.

I'm on the Mach1 harness and GT computer.. evrything seem connected and yea car is still auto

[shame302]

Well, You're all over the place on this thing, aren't ya? Have you actually had it running?

FWIW, i do not believe that manual trans, Mach 1 harness will work with your auto. This is probably your issue.

I would generally say, use the harness assembly that matches whatever ECM you're using. Mach computer, Mach harness. GT computer, GT harness. Doubly so as the GT harness is calibrated for the auto trans. I suppose it's possible that the GT trans harness might be able to replace the Mach trans harness but iirc, and I don't really remember, but the trans harness is part of main harness. Trace it back and see if it's on it's own connector if there is one. If there is, see if the computer side of that connector has unused wires when plugged into the trans side. Hope that makes sense.

[shame302]

Originally Posted by lxh89

Sounds like you need to replace all the cluster wiring under the dash and the front body wiring harness

No

Doing the cobra swap on my car, I had to replace the ECU, Engine Harness and front body harness. I also had to modify the fuel pump relay grounding and fuel pump wiring to rear body harness to make it all work.

Recommend you start there...

The body harness that connects to the ecm on the passenger side is part of the ecm harness. It reaches the ps fog and head lights, fan MAF ccrm etc. So yes, that portion gets replaced along with the engine and trans harness that connects to it. Nothing under the dash, nothing on the drivers side or anywhere else in the car, nothing that's not plugged into the computer needs to get changed (other than pats related things like the cluster, module, key, and tumbler.) Specially if we are working with the same year cars.

I thought he had everything till I realized he had a setup out of a stick car. With his being auto and wanting to keep the auto, no bueno.

[4vCrush]

So the car starts fine.... I feel as if the car takes off in 2nd gear... I don't hear the car go thru the gears at all.. When u punch it it bogs bad.!!!! FML


They told me to get a Auto mach 1 transmission harness.???

[shame302]

Well, Like I said the Mach 1 (stick car) harness was never going to work. That's likely your next option. The GT trans harness you have might work but without having them in front of me I couldn't say for sure.

[4vCrush]

Originally Posted by shame302

Well, Like I said the Mach 1 (stick car) harness was never going to work. That's likely your next option. The GT trans harness you have might work but without having them in front of me I couldn't say for sure.

By any chance would you know if the AUTOMATIC GT and MACH1 Transmission harness are the same.??

[shame302]

Originally Posted by 4vCrush

By any chance would you know if the AUTOMATIC GT and MACH1 Transmission harness are the same.??

I couldn't say for sure but I would assume so.

[4vCrush]

Thanks!

[4vCrush]

So we ended up using my GT harness and ECU and now all gears go in perfect and my O/D turned off! all the codes are gone.. But my ABS light and TRACTION button are still on .... I replaced the Speed senor and still on..

Friend says not to go over 4k but My mechanic said it should be fine now and that he tuned it with my programmer..