04 has a bad vibration as you drive at highway speeds and is beginning to produce black smoke when you lean into the throttle and on initial startup. Feels like it has a slight miss and the exhaust note isn't the same. I did a function test with out MODIS and all the injectors were within parameters of normal PSI and I disabled one at a time to see if the engine responded differently and it responded the same way for all 6 injectors. Truck throws no codes and runs like crap. Does anyone have any tips or suggestions to go about troubleshooting this? I really appreciate the help, this is my dads only DD and really needs it back on the road. Thanks in advance!