CTD2001

My fathers truck is an 02 with the FASS pump on it, i talked to him today and he said his truck has been acting up. In the morning he will get in the truck and it fires right up, then he will drive about 10 minutes to his shop and go inside. He will come out a couple of hours later and go to start the truck and it will crank and crank and not fire. He waits a couple of minutes and tries it again, it starts but it idles rough. His fuel pressure when running is anywhere between 15psi and 12psi. He said that when he first fires the truck up in the morning, the lift pump makes a nice loud whine when he turns the key and it primes the system. After he has driven it a short distance and comes out a couple of hours later and goes to start the truck, the lift pump makes a very weak whine when he turns the key and it primes the system, this is when he has a hard start issue. If he drives the truck for a long distance, shuts it off and comes back a couple hours later, the truck runs fine, although he says he can hear a slight surging coming from the engine. I told him to check over his ground and power connections and make sure they were good and clean, but i dont think that is the problem, any ideas?? thanks