What plugs did you install? Did you install OEM plugs or some aftermarket/auto parts store plugs,these engines dont like the aftermarket/auto parts store plugs.
If it isnt the spark plugs next thing i would do is see if you have a coil acting up,these trucks will run on just one cylinder, unplug all but one coil while the truck is running,yes it will throw a code but that can be cleared later,see if the truck will run on each individual coil let it run for a bit then go to the next coil.
If there is a cylinder that isnt firing correctly this will throw off the crank/cam sensing and cause this code to pop up.