I'm having similar issues with a friend's 01 Bullitt.
In your case, I would drop it at the service advisor's office of the dealer that "fixed" it and say WTF? Same issue, not fixed, thats a comeback.
If that is not what you plan to do, what was done about the FPDM? That also controls fuel delivery and pressure.
90 LX, Previous 4 cyl.
408W In the Works
TW FAC's, Jay Allen cam, Super Victor 2001 V6 5 Speed Daily Driver
Windstar Intake, Dual Exhuast, CAI, Headers
Best ET: [email protected] mph (on 18's)