check your grounds, ive had the same problem. my volt gauge will read 12 till i try to start it, as soon as the key is in the on position - it shoots to zero. check and recheck your ground. tighten all of them, even if they seem like they are good.

 

jesus christ, isn't there a ------- tech forum? this is like the 16th thread like this in the last 2 days

 

my buddy had the same problem. He parked the car for 3 months and it fired right up, lol

also thinks relay.

 

are you gettin spark? my car was doin some dumb ---- like that, and here it was the screw fell out of the rotor in the distributor, check that ---- out

 

mine used to do the same thing and it was the main relay, then onced i fixed that it would just crank and crank, come to find out the ignition switch was bad too.....

 

Had this same problem today on a saturn.... it was the starter. Check your conections close!