Location: The fuel rail is located on the top of the engine, at the back (near the firewall), and runs along the intake manifold. The fuel pressure regulator is part of the fuel rail itself; you won't find a separate sensor. To access it, you'll likely need to remove some components to get a clear view.
Important Note: Working with fuel systems requires caution. Fuel is flammable and potentially dangerous. If you're not comfortable working on your vehicle's fuel system, it's best to take it to a qualified mechanic. They have the proper tools and knowledge to diagnose and repair fuel system issues safely. Incorrectly handling the fuel system can result in injury or fire.