I have a 1998 mustang with the v6, and a vortech blower. No other modifications except for the new fuel system to feed the blower and an exhaust system. After the car has been running for a while, like an hour or so at operating temperature, if I turn it off and start it again 5 minutes later, it has a super rough idle and stalls almost instantly unless I rev it up for a few seconds (10 maybe), or if I just drive, it smooths out by itself. But if i turn it off and start it again, it will do the same thing. I am going to replace the fuel filter, but does anyone have any other ideas?