Engine miss is killing me!

[Steverino]

It did have a random misfire code. The plugs looked great and #4 looked no different. I did check the air box and it was clean, the hose from it to the TB had tears in it and a friend gave me a good used one from a 2009 Aveo which is just a bit different but works. I cleaned the TB very well when I changed the intake manifold gaskets and did an in the car cleaning about a year ago also. I use an actual TB cleaner spray and an old tooth brush. I looked at the intake valves through the head when the intake manifold was off and they looked very clean. I was going to put the vacuum gauge on it and do a leak-down test. I am not sure what a block test for combustion gas is?