How to fix code P0604 on 2001 7.3 diesel ?

SOURCE: f250 diesel running rough

The only way to find out is to take it to a mechanic who has an engine analyzer and the rubbing could be caused by a loose mudshield (or a dozen other things).

SOURCE: engine quit while driving

You will need to check every ground wire! Remove and clean each one. There are so many, too many to list! Frankster016

SOURCE: fuel guage quit

the sender unit in the fuel tank has given up the ghost ,replace unit

SOURCE: 2002 ford f450 7.3 diesel runs ruff and has

P1316 Injector Circuit/IDM Codes Detected .....FJ9 DIAGNOSTIC TROUBLE CODE (DTC) P1316 INDICATES THAT CODES ARE STORED IN THE IDM
Possible causes:
Injector(s) or circuit(s)
Open or shorted IDM enable circuit
Open/short in EF circuit
Open/short in FDCS circuit
IDM relay
IDM powering circuits
IDM
PCM
Check for other codes.
Key on, engine off.
Perform KOEO On-Demand Self Test.

This tells me that the IDM DOES store codes.
Trying to make sense of this. Which test will then give me the codes stored in the IDM? I am pretty sure we did the self test and did not get additional codes

SOURCE: 1999 ford explorer misfire in cylninder 6 code

you might try changing the engine coolant temp sensor. could also have defective spark plugs. check the fuel filter, lines and pump.