ok i have a 1990 mustang 5.0. just recently when u start the car the rpms jump form 1500-200 then the car dies. and know when i drive it the rpms jump form 4000-200 back fiers dies then wont start for 2-3 min. ALSO DOES NOT DO THIS ALL THE TIME IT DOES IT 75% OF THE TIME
i have replaced:
EGR 1 WEEK
DISTRIBUTOR (2 MONTHS AGO)
ICM (1week AGO)
COIL (1 WEEK AGO)
PLUGS (1 MONTHS AGO)
WIRES (1MONTH AGO)
CAP/ROTOR (2 MONTHS AGO)
FUEL FILTER (2 MONTHS AGO)
FUEL REGULATOR (2 MONTHS AGO)
WATER PUMP (6 MONTHS AGO)
(CLEANED) EGR AND AIR IDLE CONTROL VALVE

ALSO MY ENGINE LIGHT HAS BEEN FLASHING ON AND OFF FOR SOME TIME NOW BUT NOT EVERY TIME I DRIVE THE CAR .

 

Check your ignition components. Firing order on your stang: As you are staring at the car from the front. Piston #1 is first on the left, followed by 2,3,4. then on the right is 5,6,7,8. Make sure they match your distributor firing order, and you installed your cap/rotor and distributor right. Also, when was the last time the car ran and drove fine. That can help pin point some problems. Ignition is a good place to start though, especially if you recently ****ed with it.

 

Does it do the same thing before and after changing all that you did?