what would cause engine to not crank in 2006 300 2.7l

Nothing we can add that will help much since a mechanic has your car and can check it out hands on. All we can do is guess at the many possibilities why this happened and that doesn't really do any good. Post the mechanic's findings then we may be able to be more helpful. I hope it's not too bad, so good luck with it!

agree with #1

having same problem with my 300 2.7 took same to dealer and still have problem was told by another the computer need re flashing read on the internet that the problem might be in the fuel tank after fill up the car will stall and cut off . But I can wait about 30 min my 300 will start up and I can go another 20 min before it cuts off agin