Missing on the 6,8 I have done everything. Please help

[bctom]

Replace the plugs that are sparking yellow. I've had brand new plugs that were bad right out of the box.

I read that you cleaned them but didn't see any mention of replacements. If not then change just the two that are acting up and see it that helps.

To check for a vacuum leak around the intake gaskets - pour some water around the suspect area while the engine is running.
The vacuum will suck the water into fuel air mixture and the motor will make a definite missing sound that will quickly stop when the water is gone from the cylinder.

For carb cleaning I use a product called Seafoam that you spray into the carb while the engine is running. It's cuts out the gum and carbon in fuel system. They make a fuel additive as well. There are lots of brands of 'tune up in a can' out there but this is the one that works best for me.

Good Luck