Low fuel pressure will ruin EXPENSIVE injectors.
Fix that crack ASAP.
Also, you said you replaced the fuel filter ................. Did you replace BOTH or only one? The one on the frame rail is the primary fuel filter. It also removes water from the fuel. Since it filters, removes water, AND pumps .... it is called a fuel conditioning module. The trucks have it in a horizontal position and the vans have it in a vertical position. That is why (on the trucks) the whole unit is called an HFCM (Horizontal Fuel Conditioning Module).
Lastly, did you drain the water by removing the water drain plug?
That pump is your ONLY fuel pump, so you need to keep it working well. Drain the water EVERY oil change and EVERY fuel filter change ...... at a minimum (even when the light isn't on)! If you still have the plug that requires a 6mm allen wrench, then you need to upgrade to another drain plug. The allen wrench plug strips VERY easily.
https://www.xtremediesel.com/hfcm-w...MI1PW9lPXd6AIVka_ICh3F8Qy-EAQYAiABEgKmIfD_BwE
If the cap is cracked, you can even pull air in. That air can cause the engine to shutdown from weak fuel supply (as well as also contribute to EARLY injector failure).
Since you have an injector code, you may already have damaged injectors. BTW no tuner will read codes very thoroughly. For $40 you can download ForScan to a smartphone and buy the required OBDII adapter to communicate with the PCM. It is a powerful tool.
Every owner of a 6.0L truck (or van) needs to install a fuel pressure sensor and gauge. There are so many ways for the fuel pressure to drop and, as stated above, that will ruin injectors that cost $200 apiece.