It will run for about 5 minutes at whatever speed you want to go, then it sputters and cuts out and goes dead. If, its in gear and you try to start with clutch/ break it will backfire. Put it in neutral and it will crank, but will not idle. Crank in neutral, and give gas it will run, soon as you let it idle down to put in gear it dies again. Wait a couple of minutes, and it'll fire right off and haul butt again for another 5 minutes or so.
Is this a sensor that's getting hot or spark plug or plug wire?