I have a '96 GT and for some reason the car runs bad when its in drive. The car will idle fine in park or neutral but when it is in drive, it hesitates at idle at a stoplight, not constantly but about every 5 seconds. The tach barely registers the miss but you can still hear the car cut out. When accelerating it bucks on any amount of throttle but clears out if you punch it and then it runs with just a small miss after reaching cruising speeds. I have already replaced the plugs and coils as this vehicle has 150k on it. Tested the fuel pressure and it puts out 30lbs, and 38lbs with the vacuum removed from the pressure regulator. I also changed the fuel filter. The plug wires have 50k on them but seem fine (at least no arc in the dark anyway). I did get code p1443 which is something to do with the purge flow sensor or solenoid, but Ford said that it wouldn't make it run like this. I cleaned out the IAC and EGR valve with no different results. I don't want to just throw parts at this, so does anyone have any ideas?