The anti-theft system is not factory, it is dealer install. You can get in under the dash and remove it. It is a very clean plug and play harness install, unlike stereo shop rat's nest installs. Should be pretty obvious what it is, if you have ever dealt with auto electronics. It goes on the ignition wire loom that comes up under the steering column. If you remove the anti-theft, you will still have the immobilizer, which is factory feature, integral in the car's ECU. By the way, make sure that you are using the transponder key, not a spare key. When you try to start the car with a non-transponder key, the kind you get at the key desk at Wal-mart, the engine will crank, but not fire. That's the behavior of the immobilizer: starter operates, but no spark or fuel. The behavior of the anti-theft system is different:it disables the crank entirely, starter will not operate. So this means, if you are getting a crank, starter is operating, you are getting past the anti-theft system, but something is amiss. I am attaching a couple of reference documents for the anti-theft system, maybe you will find something useful in there. And it seems to me, from dealing with malfunctioning anti-thefts a few times, that if your battery is not at 100% charge, this will trigger the anti-theft. So either charge it, or replace it - oops I see that you have a new battery, never mind. Also check that you have not blown any fuses while jump starting your car. This could also make the anti-theft do weird things. Also, try disarming the alarm by turning the key in the door lock. This is the method suggested in the documentation. I don't know if any of this will help, I usually end up just ripping out the system.