I just finished my ls1 swap and I went to hook up the positive battery cable and it sparked really bad. I hooked up the negative first then the positive. Any reason the battery would spark so bad?

 

You have a draw from electronics being set to 12v constant instead of 12v IGN. Youll have to sort these out or your battery will drain

 

I emailed Speartech to see what he thought, but have not heard from him yet. He is who I got my TPI harness reworked and the ls1 harness from. This sucks I am so close to starting it up.

 

Try to figure out what is powering up when the battery goes on

Listen for clicks and hums. Be sure the key is off too, you dont want to go chasing your tail if the IGN is on

Common suspects are the PCM/INJ fuses are connected to 12v battery instead of IGN. Hook up the battery and check for 12v at each with the key off. They should have nothing on them

 

positive gets hooked up first, then ground. safety first!

 

positive gets hooked up first then the ground and vise virsa when un hooking

 

I just got an email back from John at Speartech and this is exactly what he told me in the email.... "That sounds like one of the battery hookup wires is touching ground. Double check that all of the main battery wires around the battery, starter, and junction block were not accidentally bolted to ground. Since they have ring terminals on them, some assume they go to ground, when they are really positive battery wires.

I've also seen the ring terminals rotate as the bolt or nut is tightened, sometimes allowing them to touch something metal (ground) when the bolt gets tight."

 

Ring terminals should be few and far between. You have 2-5 for the power distribution block, whether or not thats still on the starter

One alt lug and 2-3 grounds on the rear of the cyl heads

 

Mine did the same exact thing, turns out it was the rubber boot at the end of the positive cable, where it hooks up to the starter, was cracked. It was making the copper wires inside the cable be exposed and touch the side of the starter which caused a direct ground. Check all your cables and make sure they are secured and that nothing is grounding itself out.