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Home >> Acura >> 1991 >> Legend Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Basic Testing >> Fuel System >> Fuel Pressure >> Pressure Testing
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Pressure Testing

  1. After relieving fuel pressure, connect Fuel Pressure Gauge (07406-0040001 ) at 6-mm service bolt location. Reconnect negative battery cable. Start engine and note fuel pressure on gauge. If vehicle will not start, but has spark and no fuel pressure, inspect fuel pump relay.
    REGULATED FUEL PRESSURE

    Application At Idle W/O Vacuum psi (kg/cm2 ) At Idle W/Vacuum psi (kg/cm2 )
    All Models 37-46 (2.6-3.2) 35-37 (2.4-2.6)
  2. Disconnect vacuum hose from pressure regulator (fuel pressure gauge should rise) and inspect for manifold vacuum. If vacuum is not present, check for restriction in vacuum port or hose. Plug vacuum hose and check fuel pressure gauge. Gauge should indicate 37-46 psi (2.6-3.2 kg/cm2 ).
  3. If pressure is higher than specified, check for pinched or clogged fuel return line between fuel rail and fuel tank. If no problem is found in fuel line, replace pressure regulator.
  4. If pressure is lower than specified, check for plugged fuel filter. If filter is not plugged, lightly pinch off fuel return line. If fuel pressure does not rise, replace fuel pump. If fuel pressure rises, replace pressure regulator.