Diesel Bombers - New Maxer From The NW

Hi, im new to your forum and would like to introduce myself. i went diesel about 9 months ago. i had it shipped up from texas. 2nd owner of a 2002 duramax crew. ive personally installed a 6 inch fabtech w/ dirt logics, kmc diesels and 35 inch toyos. cognito support kit, super steer steering upgrade, amp research steps, 4 inch d. pipe and 4 inch stainless w/ no cat (bullydog), and an airraid intake.
now i wanna install a chip. i picked up a 3 stage hypertch chip. when i went to install i learned about some dtc codes in my system. 1 is a LOW FUEL PRESSURE code p1093. im learning this could be a sign of faulty injectors, im pretty sure the dealership changed the fuel filter at its five year service, right before i got it. today i tried to drain my FF and no water came out. i guess i might change it anyway. the other code is a GENERATOR F TERMINAL/ FIELD F CONTROL code p0622. if anyone recognizes this code please let me know.
anyway im hoping to learn alot on your forum and its great to see and hear so many diesel enthusiasts. this is my first time BOMBING a diesel, but have modified my 450 race quad, my turbo civic, and basically everything i own i have either graced or disgraced with my mods. i have a feeling me and this truck are gonna have a good log run.