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5.3 Swap Ground Help

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Old Nov 8, 2011 | 05:17 PM
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Default 5.3 Swap Ground Help

I have a 2003 5.3 that I have built a standalone harness for and installed in a 1971 International pickup. I am having trouble getting it running and need some help. The motor cranks and has fire to the injectors, and good fuel pressure. When I was testing the coils yesterday I accidently hit the ground wire on the harness for one of the coil packs and the engine sputtered and ran for about a two seconds. I have added some extra grounds and cleaned the existing ones and I still have the same problem. Does anyone have any ideas what to check next? It is entirely possible that I messed up when I was wiring the engine so I think that I am going to review my notes tonight. The computer was reprogrammed by LT1swaps.com and the VATs and other non needed things were removed. Thanks for any help.
Hudson
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Old Nov 9, 2011 | 07:46 AM
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Noid the injs when cranking. This will confirm that the crank side of the key sw is powering the system.
You could also check a plug when cranking. This will verify the coils are firing.

What do you mean: "hit 1 of the grnd wires"??
If I understand that, and the engine started, then the PCM is not pulling the neg side of the coils to ground.
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Old Nov 9, 2011 | 05:27 PM
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you're grounding the wires to the cylinder head and not the valve cover or something right? Also make sure you have QUALITY grounds, run them direct to battery if in doubt. For testing purposes.
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