97 PONTIAC GRAND AM SE V-6 3.1 4DR WILL START EVERYTIME & THEN WILL SHUT OFF AS IF YOU TURNED THE KEY TO OFF. NO WARNING REALLY JUST STARTED TO DO THIS. CHANGED GAS, CAMSHAFT POSITIONING SENSOR. STILL SAME RESULTS. IF YOU START IT AND "FLOOR" THE GAS PEDEL IT WILL SCREAM TO 3-4000 RPM'S THEN JUST SHUT DOWN SMOOTHLY, NO BACK FIRE, NO BURPS, NO RUMBLE, JUST SHUTS DOWN LIKE YOU TURNED IT OFF. CAR IS A 97 WITH 195,000 MILES HAS RUN FANTASTIC FOR 2 YRS AND I MEAN JUST GREAT. DID HAVE SOME REALLY BAD GAS ABOUT 7 MONTHS AGO, & I MEAN BAD, LIKE SLUGGY WEIRD GREEN OLD GAS FROM A SMALL TOWN IN AR. HELP!!!!!!!!!!