I've got a '96 C2500, 5.7, and it's misfiring. CEL is flashing, but the code is "Random Misfire". I pulled the plugs and #3 and #5 are fouled black. The rest look good. Gap is good. Did a compression test on that bank and I get 200, 195, 190, 195, so I'm ruling out head gasket. Plus, I'm...