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Fuel Pressure

  1. Release fuel pressure. See FUEL PRESSURE RELEASE under FUEL SYSTEM. Disconnect negative battery cable. Remove banjo bolt from cold start injector fuel line.
  2. Install Adapter (J-38347) with 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. 2) Install negative battery cable. Check fuel pressure. See FUEL PUMP PERFORMANCE table. For complete Fuel System Pressure Test Procedure See DIAGNOSTIC CHART A - 7.
  5. Release fuel pressure and remove fuel pressure gauge. Install cold-start injector banjo bolt and tighten to 13 ft. lbs. (18 N.m).
Fig 1: Installing Fuel Pressure Gauge
G121591Courtesy of GENERAL MOTORS CORP.
FUEL PUMP PERFORMANCE

Application Pressure psi (kg/cm2 )
Prizm & Prism GSi (1) 38-44 (2.7-3.0)
(1) Specification listed with jumper wire installed between Black/Red wire and Blue/Black wire terminals in diagnostic connector located on left shock tower, ignition on, engine off and pressure regulator vacuum hose disconnected and plugged.