2000 mustang gt, dies while driving (warmed up)
 

hello everyone, I have a 2000 gt and it use to die about once a week while driving once warmed up. I replaced the air idle control with a motorcraft one and the issue seemed to go away. now it dies everytime I drive it and wont fire up for several mins. the shop just put a new fuel pump in it and I still have the same issue. it costed me $1000 for the pump and im bumming out wondering how much the shop will charge me to fix. its been in shop two days now and I don't think they can figure it out. any help much appreciated .