i dont blow smoke unless i floor it but the exaust is always carboned up really bad

 

Get a PCV valve from the dealer. I bought the 'good one' from advance, and STILL went thru oil like there was no tomorrow. Replace the PCV with one from the dealer, end of problem.

 

you know how much the dealer one is going to set me back

 

< $10

I'm not convinced that your plenum is not blown. Here is the end all for your plenum, do the test:
http://dodgeram.info/tsb/2000/09-05-00.htm

 

Right around eight bucks.

 

i just replaced the plenum cuz i figured that was it. plenum was blown. but ive taken care of it

 

i still dont understand the idle. could i have a bad fuel injector and be washing the walls? is there a way to test them

 

If you are still sucking oil, it will still foul plugs, and give you a miss. If you are getting misfire codes, is it for specific cylinders? Or, just random?

 

sometimes i feel like i have a mis. i would get mis fire codes with #2 cylinder when i had the old o2 sensor. but i still feel a miss but no codes

 

You will REALLY feel if you have a miss at about 45 mph, when the truck shifts into O/D, and TCC engages. It will be a pronounced vibration.

If it is consistently cylinder 2 that is misfiring, and the plug and wire look good, swap the #2, and #4 injectors, and see if the misfire moves with the injector.

Also wouldn't hurt to run a compressions check.