The Code is for a Misfire on No.8 Cylinder it Could be Injector, Spark Plug, Plug Lead or several other possibilites, to check Injector just swap to another Cylinder and see if Code moves to that Cylinder.
OK since last week I have changed the coil pack that didn't help. When the MAF is unplugged the truck runs the same so I think that can be ruled out. Breather hoses and oil separator have been changed out. I am getting spark to the plugs, maybe not enough but its there. I thought that I should have continuation through the plug wires I checked three and there was no continuation through them but the truck is not running rough enough for three cylinders not to be running. The plugs on the passengers side bank are getting black as if they are not burning the fuel from 2-8 it gets worse, 2 being good 8 being the worse. If I unplug the #8 fuel injector the truck doesn't run any worse, or better, so I am leaning toward a blocked fuel injector. Any ideas would be greatly appreciated.
What about oil pressure, Just as all this started I noticed the light flicker at idle. With the hydraulic lifters if there isn't enough oil pressure to open the valves fully; would this make the engine run rough?