Cadillac Repair: 1990 cadillac deville, cadillac deville, safety switch

Question
Everytime I drive down the street my car will start to backfire real bad, but if i put it in the start postion my car will drive like normal and the backfiring will stop, what could this be?

Answer
I don't understand what you mean as the START POSITION ?. If your referring to having to turn the ignition key a little bit forward toward the dash, This would be most liely a loose and or fault in the NEUTRAL STARTER SAFETY SWITCH located under the dash near the base of the steering column.