FUEL PUMP PROBLEMS

i have a 1990 mustang 5.0. the car's motor has been shutting completely off while ive been driving down the street (all other electrical still working) and wouldnt turn on from anywhere between 20 sec-4min. i was told it could be the fuel filter and/or the fuel pump so i changed them both out with a new filter and pump about a month ago. car seemed be be doing fine so i thought the problem was fixed.

recently it started doing the same thing so i took out and replaced the pump again since it was still under warranty. also changed the fuel filter again just to be on the safe side and its still turning off on me.

any ideas?? this car is a daily driver so i need this fixed asap or my job can be on the line. please help.

ive also checked to see if the intake tube had any water build up but was it was dry

any ideas?

i changed the tfi module, dizzy cap/rotor and spark plug cables with new msd brand about nine months ago. after the fuel pump went out last month i replaced the tfi module with a new factory replacement.

i let the car sit idling and waited for it to turn off. i tried starting it to make sure it wouldnt start. i then tested for spark today by removing the spark plug wire from the tfi module and it had spark. but i then put the spark plug wire back on and it started back up...

what is the PIP? i can try changing that if i knew what it was.