Update: Put it back together ran great for about 2 miles started making the noise agian. Then it died when we got it back to the house. Then we pulled the injector connector on #6 and it ran again but when its on it dies... we think it may be a short. Any ideas?

Ps Piston 6 looked cracked...

 

Well before you get ahead of yourself with pistons being cracked or going out. Do a compression test and see what that gives you. If you get good compression in the cylinders at least you won't have to worry about the pistons.

 

Well im not to worried about the piston as it doesn't make anysounds once the injector is unconnected. Runs fine on 5 cylinders without the injector hooked up.

 

dont be too sure of that. There's no combustion going on in that chamber so none of the parts in that chamber are under any stress until combustion is reintroduced. There could still be damage in there. Run a compression check like duowing said. But that might not tell the whole story. If you have a hotspot on #6 thats detonating then the only way you're going to find out is to pull the head. The piston contacting the sparkplug may have damaged the piston.

 

If the piston did contact the spark plug and it put a little dent in the piston, it could be creating a hot spot which will lead to detonation and eventually failure.

What did the crack look like? I assume you were looking at it through the spark plug hole?

Can you get pics?

This is when you need a bore scope!