Do you know if her '08 has a fuel pump driver module (fpdm) on the back of the rear seat?Well I found that a 2008 Taurus has fuel pump access under the rear seat on the right side. That is the good news, the bad news is the fuel pump is working but car won't start. But give it a shot of starting fluid and it fires up, but quickly dies unless I keep spraying to keep it going. So I am sending it in to a mechanic for a proper diagnosis, I still suspect a bad fuel pump but I don't have a gage to check the pressure, and I can't keep throwing parts at it because it is mother in law's car, i already put new plugs and coils on it. Because it was missing when it pulled in my driveway, and I found the plugs were shot, this was before I found it would run and run smoothly if you shot fuel in the throttle body.
If the pump can not make sufficient pressure, it will set a code. All from '02 and later use a FPDM and it regulates the pressure. The system adjusts the pump speed to provide the pressure at the engine fuel rail that the PCM wants. If t can't do that, it sets a code.Well, if the the pump is running, that rules out the inertia switch and relay, lol.