99 B2500 cannot run diagnostic. multiple issues.

[josh cloud]

i get nothing from the obd2 port. yes fuses are good. left cigarette lighter works and has voltage. also, nothing at the display in the instrument cluster, so i can't do a diagnostic from there. the truck cranks and runs, badly. there's a miss throughout the rpm range. i can get it to run decent, at slow speeds. when the truck is warm, it almost runs good. stepping on the pedal hard causes misses and backfires. i read somewhere that there's a resistor that controls the obd2 port voltage

 

[franklin2]

What engine do you have?

 

[rusty ol ranger]

What engine do you have?

B2500 is a 2.5. B3000 is 3.0 B4000 is 4.0

So he has a 2.5.

It was my understanding that if the fuse is good but the port is dead its an ECM issue.