93 d250 getrag two turns on the fuel screw two turns on the smoke and a rotated fuel pin. Timed the pump just over an 1/8 ahead. I think I have a bad injector when its cold it fires up just fine and runs on all 6 once it warms up it sounds like its dropping a piston,it has an air compressor type boom in the exhaust. I have check the valves they all measured out 0.010 on the intake and 0.020 on the exhaust also changed the fuel filter for giggles and I did bleed injectors too ....well any ideas?

 

Sound like this?

 

crack the injectors running one at a time, see if it changes.