Hit it with a hammer (lightly)
its completely temper mental. Bought the car, started fine for the guy, started fine for me to get it home, started fine for me to get it to the girl friends house, then didn't start at her house after i got there... started the next morning... then all that day till that night wouldn't start again.. started all the next day... then all yesterday! till last night when she got to my house... what a frigging piss off i tell you. I don't think its the engine being seized.. she was just driving it and shut it down for a few.. and wouldn't start.And yes on the backside of the engine.... underneath the exhaust mani... and behind a heat shield! lol what a PITA
Check the wires, they can cause that problem. Basically the solenoids don't have enough power to get the starter turning. When you hit it you are reducing the friction and then she has just enough. 15 minutes with a voltmeter and you'll know if the wires are to blame.