97 Chevy Silverado, Running on 7 Cylinders

I had to replace the intake manafold gaskets on my 97' Chevy Silverado 5.7 liter V8. I was having overheating problems and checked the pressure in my cooling system and found the problem. Anyway, That being fixed, I got it back together and running but it was running a little rough and the check engine light came back on. I went and had the code read and it said the 2 cylinder was fowled. I replaced the rotor cap & the plugs. The Plug wires are new so I switched the wire with another wire to see if the other cylinder would do the same thing. It didnt. The new 7 plug was wet with gas. The truck starts up on a pinch and runs but is running rough. And has a little shake on exceleration. Not bad enough to drive but it is eating the gas.

Could it be a sticking valve? I have 178,000 on the truck. If the valve is not seating what should I do?
If its not what I am thinking do you guys have any suggestions?

Bofreddy?