Hey one my guys ran the truck out of diesel. Now im having trouble with it.Its a 1998 MITSUBISHI FE434 Body Style: TILT CAB Engine Type: 3.3L L4 FI Manufactured In: JAPAN I'`ve change the fuel filter. bled all the injectors. I dont know what to do with it now. What happens is it will sit and ideal fine. But I start driving it down the hwy when I get it up to about 55mph. It will run fine for about 3 minutes or so. Then the rpm will start to decline and go back up back down then it will just decline and the truck will start to slow down. I stoped pulled the fuel filter back off and its full of fuel. One time it was like half way full of fuel. I'm not sure what is wrong. Any Ideals?