My daughters boyfriend has a 2014 Camaro SS and had the exact same issue with the misfire on Cyl 4 and random misfires. We changed some of the same parts as mine and it ended up being a broken valve spring. I didnt dig that deep into the issue, we sent it to a local shop that he chose which raked him over the coals. They are charging him $1100 for the repair. The only broken/damaged part is the spring and possibly the push rod. They pulled the head and thats where the costs doubled.
I will check to see of my MAF is the same from my tahoe and swap them tomorrow. I dont want to get into swapping too many things with my truck, I still need to get to work
