2002 7.3 trouble codes
I have the following trouble codes for my 7.3: P1670, P0603, P1247, and P1211. the engine will run OK for a mile or so and then really misses. The last time out, I had to go to creeper gear and low range to get up a small hill, that normally the truck will climb in 5th gear. I have noticed today when I read the codes, that the lift pump is getting noisy. Some research indicates IDM, other indicates valve cover wiring harness. I have Superchip performance tow installed. Any help?