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Fuel System Pressure

  1. Turn engine off and relieve fuel pressure. See FUEL SYSTEM PRESSURE RELIEF. Remove air cleaner and plug air cleaner (THERMAC) vacuum port (if equipped).
  2. Disconnect fuel line between throttle body and fuel filter. Install Fuel Pressure Gauge (J-29658A) and Adapter (J-2968A-85) between throttle body and in-line fuel filter. Start engine and observe fuel pressure reading.
  3. Fuel pressure should be 9-13 psi (.6-.9 kg/cm2 ). If not, see CHART A-6, FUEL SYSTEM PRESSURE TEST in the CCC TBI TESTING/CODES article in the COMPUTER ENG CONTROL section.
  4. After testing, relieve fuel pressure. Remove fuel pressure gauge and connect fuel line to fuel filter. Start vehicle and check for leaks. Remove plug from throttle body vacuum port (if equipped). Install air cleaner.