1989 Ford Taurus WILL NOT START

Engine Mechanical problem
1989 Ford Taurus 6 cyl Two Wheel Drive Automatic

CARS BEEN RUNNING FINE, THEN JUST CHOKED OUT AND QUIT. IT TURNS OVER FINE BUT NO FIRE WANTED TO ONCE BUT NO MORE. WE HAVE CHECKED FUEL PUMP ITS GOOD, THE FILTER IS O.K. I'M GETTING GAS TO THE CARB. ONE "MEC." SAID PLUGS MIGHT BE FOULED SO WE PUT IN NEW PLUGS, CAP, ROTOR WE ARE GETTING SPARK TO PLUGS, SO ONE "MEC." SAID MIGHT BE TIMING CHAIN SO WE CHECKED THAT, ITS O.K. TIMED IT, ITS O.K. BUT STILL WON'T START. SO THIS "MEC." SAID IT PROBLEY IS THE BRAIN. WHAT DO YOU THINK?