Ford E6TZ-9C968-B Regulator Assembly

EFI models maintain constant fuel pressure from the fuel pressure regulator by causing resistance beyond the injectors, thus allowing some of it to go back to the tank. It can vary its restriction through engine vacuum, a diaphragm, and a spring as engine requirements change. Additionally, when the fuel pump is not running, the restrictor closes very fast and acts like a check valve thereby aiding quick engine restarts. For proper functioning, fuel flow should be unblocked, an open return path must exist along with a dependable vacuum signal. Failure can result in overpressure or underpressure which are caused by contamination or valve malfunctions.

Depressurize fuel system and remove shielding as needed. Disconnect vacuum line at pressure regulator. Remove fuel return line if necessary. Remove Allen head screws from regulator housing. Remove regulator assembly, gasket, and 0-ring. Discard gasket and check 0-ring for cracks. Clean mating surfaces. Lubricate 0-ring with engine oil. Install new gasket and 0-ring on regulator. Install regulator on fuel manifold and tighten screws. Install fuel manifold shield and tighten bolts. Connect vacuum line and fuel return line if removed. Build fuel pressure by turning ignition ON and OFF five times. Check for fuel leaks.

Failures in the regulator can include contamination, vacuum diaphragm leaks, or valve malfunctions.