Here's a little PSA for ya:
If you need to transport your gas grill, it's best to do it with a trailer or in the back of a pickup truck. If you MUST put it inside your car, do yourself a favor and TURN THE GAS OFF.
If you forget to turn the gas off, DON'T LIGHT A CIGARETTE!
That's what happened to a couple in Orlando...they had a gas grill in the back of their car, with the gas on, and then all you-know-what broke loose when someone lit a cigarette. The fumes from the propane and the flame from the lighter went BOOM and caused a massive explosion while the car was headed down the road.
Both people in the car will be ok, and to many of us, it's pretty self-explanatory not to have open flame near a flammable gas....but just in case...I wanted to put that out there! (yes, that's a photo of the actual car)