I recently purchased an '02 2500 HO but am not getting much power. I can't get it to smoke (which is a good thing I guess) which makes me think I'm not getting enough fuel. What steps should I take to fix this problem? The dealer says the pump is in the tank but I don't know if I believe him but this is my first diesel and am not sure. I've been told that the valves should be adjusted every 100000 miles. Is this something I can do with basic hand tools?