I just got done putting the LS1 back together and now there is arching going on between the passenger side valve cover and the head. I thought it might be the coil which was arccing earlier too, but I replaced that and it is still there. What could it possibly be, a bad ground???? I'm lost, please help me here.

 

If it's arcing as in high voltage, then there's a bad wire or plug.
Electricity takes the shortest path to ground.

 

It's not arching out of the plug though, it's arching from the actual head to an accessory bracket.

 

when the boot on my alternator wire (the hot wire) rotted away it was arcing onto the valve cover, that could be a possible source.

 

Spray water on the wires in the dark and move them around.
Maybe you put a slit in one or pinched it.

 

What would spraying water do?

 

nothing that I can think of. if its arcing, you can see it in the dark just fine. in fact putting water around the area could make it harder to find if the water is closer to the short than where its arcing

 

What I don't get though is why it's arching from the head to the accessory bracket, and I see no arching at all from any of the spark plug wires. Also if it matters it is also arching in another spot further back on the engine that I can not see real well.

 

I just say follow the sparks. if it's arcing from another place behind the engine that means its gotta be running through the there but not grounding out for some reason

 

I'm starting to think I got a set of bad plug wires?

 

The fact that there are sizable arcs between the head and accesory bracket is really wierd... The head should be pretty much as grounded in the car as you can get unless there isnt a good ground going from the engine to the battery.

 

Well I feel so stupid now! Relieved at the same time too. The very rear passenger side spark plug wire had fallen off and since it's so crowded I couldn't even see that it had fallen off and was causing the arcing. Thing runs like a raped ape again! I love having over 500 hp at the blip of the throttle.