New to ATVs

Hi Guys,
I bought a 2013 TRX420FPE ES right before Thanksgiving. This is my first ATV and the first experience with fuel injection. I haven’t started it since I bought it and I’m having a problem getting it to run. It starts for a few seconds and stops. I suspected bad gas and drained the tank. I’m just not sure how to purge the rest of the system. I think I should be able to take off the line to the fuel injector and turn the key on and the pump should run as long as the key is on. Am I on the right track?