misses under throttle...

[kunar]

well, i have had a small miss under heavy throttle for a while now. it has always been only when the truck had sat for a while (atleast a day or 2) and its always went away after just a few minutes. i figured that since its burning oil (im not sure why yet) the plugs were getting damp, and the miss went away after the oil burnt off. well a few days ago, the miss started to go away, then it came back worse than ever. i thought maybe i had a spark plug that wasnt sparking, so i took them off one at a time and ran the engine, but it seems like they are all doing something. i havent pulled any yet though. i have checked for codes, and heres what i came up with

31 - EVP circuit below min voltage
-
63 - TP circuit below min voltage
32 - EVP voltage below closed limit
29 - insufficient input from VSS
-
31 - EVP circuit below min voltage
77 - operator error - dynamic response/cylinder balance

now i have always had one code or another that was telling me my egr wasnt working right. im assuming that TP is throttle position. ive replaced the tps with a known good used part. i dont understand why i would have a vss code, i dont even have a vss. and as for the 'goose test' i gave it full throttle when i was prompted, im not sure why it would say theres an error. anybody have any input?