My 2003 town and country 3.3 v6 flex fuel 2 wheel drive trys to start up, sometimes it runs for few seconds and dies. Just replaced fuel pump, fuel filter, spark plugs and had the starter tested. It's getting fuel from the fuel filter but not at the fuel rail except every once in a while it gets a small amount than back to nothing. Was told my van don't have a serviceable regulator its part of the fuel filter. Any suggestions of what it could be? What all to try next?