I had a similair situation in which I couldn't get finaincing to anyone to talk to me. I was a student with plent of money but that didn't matter.
I got out of school and started my job(had it locked in when I was looking for a car). Now people are falling head over heels to sell me a car and give me credit cards. If you want credit you have to play by their terms. I support their harsh attitudes only because they need to be harsh to prevent the kinda crap that was happening with giving out too many loans to people who couldn't afford them. It's also helpful to understand, a loan is almost no different then a loan from a friend. They are doing YOU a favor, not the other way around. So don't be mad when they say no
In all honesty, if you aren't willing to wait until you start your job to get the car that kinda throws up a red flag. Like "why does he want it so bad RIGHT NOW..." Just tossing in my 2 cents.