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Fuel Pressure

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 1995 Mercury Grand Marquis, 1995 Mercury Cougar, 1995 Lincoln Town Car, 1995 Lincoln Continental, and 1995 Ford Thunderbird. However, it is still accessible from the selected car via links, so may be relevant.
WARNING: ALWAYS relieve fuel pressure before disconnecting any fuel injection-related component. DO NOT allow fuel to contact engine or electrical components. See FUEL PRESSURE RELEASE.
NOTE: For fuel pressure specifications, see FUEL PRESSURE SPECIFICATIONS article.
NOTE: For additional fuel system testing information, see SYSTEM & COMPONENT TESTING -- EEC-V article.
NOTE: See the appropriate TESTS W/CODES article in the ENGINE PERFORMANCE section for diagnostic procedure of the PCM-fuel pump circuits.
  1. Visually inspect fuel system, including fuel lines, connections, injectors and electrical connections. Ensure Inertia Fuel Shutoff (IFS) switch is not tripped. Check condition of battery and fuses. Ensure fuel level in tank is sufficient.
  2. Turn ignition off. Release fuel pressure. Install fuel pressure gauge. Start engine and increase engine speed to 2500 RPM. If engine will not start, cycle ignition switch several times. Record fuel pressure. For fuel pressure specifications, see FUEL PRESSURE SPECIFICATIONS article. If fuel pressure is as specified, go to next step. If fuel pressure is not as specified, see SYSTEM & COMPONENT TESTING -- EEC-V article for fuel system diagnosis.
    NOTE: For additional fuel system testing information, see SYSTEM & COMPONENT TESTING -- EEC-V article.
  3. With fuel pressure gauge still installed, cycle ignition switch on and off several times. Record fuel pressure. If fuel pressure is at least 25 psi (172 kPa) after one minute with ignition off, system is capable of maintaining fuel pressure. If fuel pressure is not at least 25 psi after one minute with ignition off, test fuel injectors for leakage. See FUEL INJECTORS.
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