check engine light giving random codes?

[hotmilk400]

okay, i have a 1998 318ti, and it runs FINE, no problems, maybe a new clutch. anyway, my check engine light had gone on awhile ago, it said fuel injector 3 was open. (which it was fine) anyway, i let it go, and after awhile, it turned off BY ITSELF. then like last week, the light went on again, and the codes are uknown , code 96 an code 00067.

these random codes seem to be activated when i turn on the A/C (which dosnt work/isnt cold)

both times, the check engine light went on because i turned on the A/C.

when i bought the car, that button was MISSIN, and the kid was having trouble with stuff like this.. (i think he removed the switch so it wouldnt happen) anyway, is there a reason my a/c would create random codes???

also, my a/c doesnt work.. wanna tell me where to start when it coems to fixing it.. the first time i used it, it was cold for alittle, then it wasnt.. then it randomly blew like 5 fuses, now its jsut doesnt work, but if its runs, it like makes the temperature of my car's motor decrease (alot) so i dont know .. haha.. i just dont use it anymore because i dont want it to destroy my car.. am i at the point that i should fix it, let it alone, or pay someone to remove it completly.. because its just holding my car back being there.. the problem comes in teh summer when my car is 120 degrees and my black seats dont help.. (and the windows are broken, because im to lazy to fix the dump plasic piceses .. AGAIN.. haha.. )

any help would be AWESOME =]