hi folks. i'm on a trip, about 5 hours from home. have tools (will travel?) 72 triumph tr6 with lots of goodparts the gas gage goes left when i turn the car off, and then goes to 1/4 when i turn the car on. period. irrespective of how much gas is in the tank. just all of a sudden as far as i can tell. what do i look for? where do i start trouble shooting? thanks!