I have a 00 1500 5.9 4x4 that idles ruff as hell. It clears up some if you keep the rpms up but it has thrown different codes. First time it was injector open cylinder 1&8. Cleared those codes and swapped plugs on injectors and didn't get anything. Plugged the injectors back in right and started it and got injector open cylinder 8&4 plus vehicle speed sensor. Cleared those codes and ran it again and got the same codes. Some said computer but I'm not sure. Oh it also fowled all the plugs and has dumped so much fuel it's in the oil and you can smell raw fuel in the exhaust while it's running. Any help would be appreciated

 

Check that the engine coolant temp sensor is doing it's job.

Change the oil.

Verify that you are getting 12 volts to the injectors in question, and that the computer is actually trying to pulse them. (either get a noid light from the parts store, or just use a test light. noid lite is better....)

If the PCM isn't firing the injectors, verify the wiring is good.

If the wiring is good, PCM is highly suspect.

 

All injectors are firing. And I tried a tps sensor but nothing. I'm gonna put some plugs in it and see if that help cause they are all fowled

 

Oil, or gas fouled?

 

The new plugs will just get fouled too. Figure out whats up with injectors. By swapping plugs on injectors, do you mean you put the injector wire for 8 on 6 and 6 on 8 etc??
You can also check ohms on injector prongs, they should all be the same. If six are 12.4 and two are 19. something, then they are bad.

 

I'm pretty sure that they are fuel fowled. I checked the injectors with a nod light and the were all hitting. I put on a new tps sensor which seemed to help but the plugs are bad so I can't tell if it took care of it. I'll ohm out the injectors after work and see what that does. Do I ohm them while there plugged in or just ohm the plug? And yes I swapped the plugs from 8 to 6 and 1 to 3 the first time and it didn't throw a code after about 5 to 10 mins running so I put them back and ran it and within minutes it threw the injector open code on 8 and 4. Cleared those codes and ran it again and again I got the same codes. 8 and 4 plus it threw a speed sensor code both times. I was told it was the computer but I don't wanna spend 400 and that not be it.

 

You want to test resistance of the injector itself, so, unplug the connector, and test resistance across the terminals on the injector. Should be around 12 ohms.