The most likely suspect when the problem is intermittent is the neutral safety switch on the transmission. Also, if someone has been poking test leads into the terminals for the starter relay socket, those can easily become stretched and make intermittent contact. I don't have access at the moment to a wiring diagram, but all of the preliminary testing can be done at the starter relay's socket. If you need help with that, I should be back within the next two nights.
Try shifting to neutral, then cranking the engine.
Read this guide, it will help you narrow down the issue
The wiring diagram for your starting circuit is attached below
Friday, July 10th, 2015 AT 6:24 PM