Pontiac Trans Am 1979 150,000 miles 6.6 L 403 olds engine.... i need to know what is going on... my car when i start it up will idle fine in park or nething but once my car goes into gear (its an automatic) so once i put it in reverse or drive and let off the brake it dies.... unless i put the gas ALL THE WAY to the floor... if i put the gas to the floor the car starts moving and runs... until i let up on the gas to much and then it dies.... PLEASE HELP ME... im thinking a carb. problem.... maybe the idle is set to low i d k lemme kno plz