Rep Power: 0

I have a 2007 Civic LX that's giving me a lot of problems and I'm not sure what the problem is. Car was running great, but I noticed what felt like a transmission shudder between 50-60mph. While driving one day the CEL came on and then started to flash, I lost power, so I pulled off the road and turned it off. I let it sit a couple minutes started it up and it drove fine. A month later, while driving it I lost power and 30mph was max speed, the CEL was flashing with P0304 code (misfire on 4). The problem didn't get any better, now I can press the accelerator to the floor there's no change in RPM. I've replaced spark plugs, coils, injectors, fuel pump assembly, and it has a new air filter. I'm not sure what else to check or what's causing the misfire and no power. If you have any ideas I'd greatly appreciate it. I've also checked the MAF by unplugging it and the car turns off. Any ideas are greatly appreciated.

 
Rep Power: 228

Did you find what you're missing though?

Fuel or Spark?