Ok so I had a misfire code for number 4 cyl. I have some spare good injectors. Swapped out number 4 no change. Changed it out again with another injector no change. Checked voltage at pigtail reads same as number 6. Truck has heavy white smoke at idle and raised rpm. If you unplug #4 when it’s running little to no change in motor sound. Checked fuel rate and injector rate with tech 2. All the injectors and the calculated fuel rate (mm3) is all over the board. Calculated fuel rate is from a 2 to 19,20. Pulled oil fill cap Incase it was a cracked piston no excessive crank pressure. I’m lost harness looks good. Truck is a 06 lbz with 367000. Any help would be great.