I had a guy bring a 2001 F-250 7.3. The truck could hardly get off the trailer. Smoking bad. He said a shop told him he needed a SET OF INJECTORS. After checking, with AE. I found the valve cover harness was bad. The shop wanted $1500.00 to fix it. Just don't take their word for it. Check it out - If it don't sound right, its not.