Hey fellas. So I just bought a 97 f250 7.3 auto 4x4. When I got it the engine was bad so it has a newish engine from a wrecked truck. The problem I'm having now that I need help with is the truck is running incredibly rich, shaking at lower rpms (not enough power for the load), feels about half the power it should. What I've done is pulled codes, I got #3 cylinder contribution fail, then I played musical injectors to see if the problem followed, it didn't. I changed the idm, no change. Changed the valve cover harnesses, check the resistance on all the wires and sensors. I should add that I got code P0476 exaust pressure control valve ckt range as well. I did do a buzz test. They all buzzed, some sounded different but still buzzed. Compression test was good I'm new to diesels and I could use some help. Thank you guys in advance