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Modify GT harness or leave this running 4V alone?

582 views 0 replies 1 participant last post by  meanmug 
#1 ·
Hey all, I have a 96 GT that we put a 98 Cobra engine in. It is currently using the cobra engine harness and a cobra PCM, we also put a 255 Walbro fuel pump from another cobra in the tank. The rest of the wiring is the GT's such as the PCM harness and in dash harness. Surprisingly the car idles smooth, revs smooth and is totally driveable, but it definitely doesn't have the greatest power. The O/D on light comes on as well even though it's a manual. I don't have to worry about PATS since it was disabled in the cobra PCM.

I have 3 codes which are p1000, p1232 and a code for the air pumpbut the air pump is completely missing from the car. I am in the process of deleting the air diverter valve since I'm not worried about it being street legal right now.

So the only code that worries me is the p1232 Low Speed Fuel Pump Primary circuit malfunction. I don't know if the PCM is bad or there is no work around this code or proper function of fuel since the pinouts on the harnesses are probably different. These are the only issues I have.

Now the only thing left to do is bring the car to get dyno tuned but, my question is, should I bring the car as-is for a tune since it's actually running? Or should I modify the GT harness and use that, as well as the GT computer and delete IMRC's etc?

If I'm better off using the GT harness, I've searched and searched and I'm not finding specifics on how to do a couple of modifications.. such as, what exactly do I need for the alternator plug (I have both GT and Cobra harness), are fuel injector adapters needed? Switching polarities on the coils are as simple as switching the left wire to the right side and vice versa on both? (but if I have both the 4v coils and 2v coils would that modification be necessary? Would putting the GT coil packs on the cobra motor solve that problem?)

I totally suck at electrical stuff.. if I could pay someone to take it from here I would but i'm having a hard time finding the help and that's why I came here :)

Extra harnesses and parts I have on hand are:
In dash harnessout of 97 cobra
96 GT battery and fuel injector/engine harness
96 GT 2v Coil Packs GT PCM

(currently running 98 cobra harness which came with engine as well as 4v coil packs)

Thanks in advance for your help!
 
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