Having a problem with a 1997 GT with 220k that has no engine start. The car died after driving 45 miles on highway, left with 1/4 tank of gas. Got to off ramp light and tank was on empty mark then car died when stepped on gas. Car would not restart but cranked normally. Refilled with 5 gallons of gas and still no start. The timing belt is intact and has 70k on it, as do the tensioners and rollers. Car has spark at coil and plugs, as precaution replaced with NGK's plugs, starter is only 6 months old as is fuel filter. Also car does start on starting fluid but dies right away, and throws out no engine codes. As a precaution did replace Crank and Cam position sensors. Haven't checked fuel rail pressure, yet. Could it be a weakened fuel pump or air in the lines, or bad relay?