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Fuel Pressure

NOTE: For fuel pump specifications, see FUEL PUMP PERFORMANCE table.
  1. Release fuel pressure. See FUEL PRESSURE RELEASE. Disconnect negative battery cable. Remove banjo bolt from cold start injector fuel line.
  2. Install Adapter (J-38347) and 2 new gaskets. See Fig 1. Tighten adapter retaining bolt to 13 ft. lbs. (18 N.m). Install Fuel Pressure Gauge (J-34730-B). Ensure shutoff valve is closed on fuel pressure gauge.
  3. Install negative battery cable. Turn ignition on. Install jumper wire between "B+" terminal and fuel pump terminal of diagnostic connector located on left strut tower. See Fig 1. Check for fuel leaks.
  4. Open fuel pressure gauge shutoff valve. Open fuel pressure gauge air-purge valve to bleed trapped air/fuel into container. Close air-purge valve. Check fuel pressure. See CHART A-7 under DIAGNOSTIC CHARTS.
  5. Release fuel pressure, and remove fuel pressure gauge. Install cold-start injector banjo bolt, and tighten to 13 ft. lbs. (18 N.m).
FUEL PUMP PERFORMANCE

Application psi (kg/cm2 )
All Models (1) 38-44 (2.7-3.0)
(1) With ignition on, engine off, pressure regulator vacuum hose disconnected and plugged, and battery voltage applied to terminal FP in diagnostic connector (located on left shock tower).
Fig 1: Installing Fuel Pressure Gauge
G121591Courtesy of GENERAL MOTORS CORP.