Ok guys.
I have 1990 Firebird v6 and recently some tard tried installing a amplifier in my car. Well after he said it was installed i got in the car to start it, well not a dang thing. The starter turns over but the car wont run. The car still has power with the ACC i the on position but get this, i have no heater control working nor stereo or the real kicker the check engine light thats supposed to come on wont even come on. After doing the obviouse checks i replaced the battery, Igntion control modual and all the fuses in the panel but the car still doesnt react. The only thing i can think of is that it fried the Engine control computer. Short of spending the money on replacing im hoping i get some replies back from someone who might know the problem. apprciate any help thanks. UPDATE...ITS FIXED, turned out to be a disconnected small wire near the battery terminal that was in some wire gaurd. Thanks to all the peopl who gave me tips, i apprciate it alot.

 

Did you check the fuse by the battery ? It's right off the main + cable in a weaherpack connector (on the firewall I think). There's a 20A fuse in there that the ECM & a few other important relays get their power from.