You should check the meth at the nozzle and make sure its still working. I have seen more then a few meth kits that appeared to be working, pump running, and activation light lit up, but nothing was coming out of the nozzle. If its not spraying then that will cause a lot of problems. By the looks of your plugs that would be one of the first things I would look at.

How many total psi of boost are you running, and how much timing?