Where is the fuel pressure regulator located on a 2004 Kia Optima?
The fuel pressure regulator on a 2004 Kia Optima is integrated into the fuel rail. This is common in many modern vehicles; it's not a separate component you'll find easily accessible. You'll need to access the fuel rail itself to reach it. This requires working on the fuel system, so safety precautions (disconnecting the battery, etc.) are crucial.