I have a 1997 chevy cavalier. it is my first car and i love it to death. the problem is that it will not run unless i have a code reader plugged in to it. when the code reader is plugged in everything works fine and she runs great but if i unplug it while it is running all of the dash lights will come on (oil, battery, airbag, etc...) and the heat and a/c dont work. if i unplug it before i start it the car will simply turn over and then shut off. i have changed the cam and crank censors, the air bag computer and the pcm. does anybody have any ideas?

Have you tried pulling the codes from the computer?

Scott

i tried to but the code reader isnt actully showing any codes at all.

Without first hand diagnostic capabilities, my guess would be the problem lies int he Passlock antitheft system. Once you get it running, attempt a bypass on that system. It's not that hard if you check out this website and follow the instructions.
http://www.the12volt.com/installbay/forum_posts.asp?TID=99218&KW=wlmpwlmp

thanks for the idea, i will give it a shot