My truck sounded exactly the same way and had no power. It turned out I had 1 bad injector. Take the two fuel lines off the bowl that go to each head and put a balloon over each, sealing them with a wire tie. Take the fuel pump relay out so it doesn't pump fuel. Have someone crank the engine while you watch the balloons. If the balloons inflate at all you are getting compression back thru an injector which is pushung air thru the rest of them. See which balloon inflates and follow it to that bank. Now remove all glow plugs but one on that bank and crank the engine, moving the one glow plug down the line of cylinders until you find the one which is pushing air back to the fuel bowl. That's your bad injector.