the other day i go to start my car (91' V6 Firebird) wouldnt start, i go to work turn the key and it works, then it dosnt the next time i try, i thought it was the battery, so i went and bought antoer one, diddnt work, i cleaned the terminals, then it worked again, went to try again and it diddnt, what do ya think, could it be loose wiring (if so witch one?), or a bad terminal, someone please help, thank you

One other thing, when i romp on the gas, or when it shifts hard, i hear a loud thud, and the whole car shakes, is that my tranny mounting block????

 

Dude that sucks! Sounds to me like you have a short somewhere (if it's only doing it sometimes) I would first check out the ignition unit on your collum (see if making good contacts) then you'll probably have to start tracing out the wires and look for shorts. I'm in the process of trying to figure out why my exterior lights wont work (one day they just stoped working. Electrical problems SUCK!!! Just remember that the electrical system itself is simple, it's only difficult because the wires are so hard to get to, be pataint, carfull and try and stay SANE! Good luck.