Fuel Injection Pressure Regulator Delphi FP10559. See our other listings. Fuel Injection Pressure Regulator. Precision is key for the fuel pressure regulator on any vehicle. At Delphi Technologies, we use OE engineering to test our regulators and fuel technologies to ensure the utmost performance and durability. Our NitrileTM diaphragms are resilient against high-ethanol fuels, and […]