My truck only smokes when I have the max HP tune on and it only smokes a tiny amount, it wastes fuel if you have a rolling coal type of tube I wouldn't imagine you are burning through alot of fuel as it's just dumping it into the cylinders.
As of dealt with this code before unfortunately you're pretty much chasing a wiring gremlin if your truck happens to be deleted you can program it out as it doesn't need fuel temp sensor to run properly with all the emissions taken off of it.