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Fuel Pressure

NOTE: All models use in-tank fuel pump.
  1. Ensure battery is fully charged and ignition is off. Disconnect negative battery cable.
  2. Note location for fuel pressure gauge installation. See Fig 1. Fuel pressure gauge may be installed on fuel filter or on delivery pipe depending on model application.
  3. Place container under fuel filter or delivery pipe. Cover union bolt with shop towel. Slowly loosen union bolt to release fuel pressure.
  4. Remove union bolt and gaskets. Install Fuel Pressure Gauge (SST 09268-45012) using NEW gaskets. See Fig 1. Tighten union bolt. Reconnect negative battery cable.
  5. Remove cover (if equipped) and install scan tester on data link connector No. 3. See Figure. Turn ignition on. DO NOT start engine.
  6. Using scan tester manufacturer's instructions, activate fuel pump and note fuel pressure. Fuel pressure should be within specification. See FUEL PUMP PERFORMANCE  table.
    NOTE: Fuel pump may also be activated by connecting battery voltage to specified terminals on fuel pump. See Figure.
  7. If fuel pressure exceeds specification, replace fuel pressure regulator, located on the delivery pipe. If fuel pressure is less than specified, check for defective fuel lines, connections, fuel pump, fuel filter, fuel pressure regulator or fuel pressure control Vacuum Switching Valve (VSV) if equipped.
  8. Turn ignition off. Remove scan tester from data link connector No. 3. Reinstall cover (if equipped). Start engine and allow engine to idle.
  9. Disconnect and plug vacuum line at fuel pressure regulator. Note fuel pressure. Fuel pressure should be within specification. See REGULATED FUEL PRESSURE  table.
  10. Reconnect vacuum hose on fuel pressure regulator and note fuel pressure with engine idling. Fuel pressure should be within specification. See REGULATED FUEL PRESSURE  table.
  11. If fuel pressure is not within specification, check for defective vacuum hose or fuel pressure regulator. Shut engine off and note fuel pressure.
  12. Fuel pressure should hold at least 21 psi (1.5 kg/cm2 ) for a minimum of 5 minutes. If fuel pressure does not hold as specified, check for defective fuel pump, fuel injector or fuel pressure regulator.
  13. Disconnect negative battery cable. Remove fuel pressure gauge. Reinstall union bolt using NEW gaskets. Tighten union bolt. Install negative battery cable. Recheck for fuel leaks.
Fig 1: Installing Fuel Pressure Gauge
G95H31614Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
NOTE: For more information on checking fuel injectors and other fuel sub-systems, see SYSTEM/COMPONENT TESTS article.
FUEL PUMP PERFORMANCE

Application Pressure psi (kg/cm2 )
Land Cruiser, LX450 (1) 38-44 (2.7-3.1)
(1) Check fuel pressure with engine off and using scan tester connected to data link connector No. 3 with ignition on to activate fuel pump or by connecting battery voltage to terminals on fuel pump.
REGULATED FUEL PRESSURE

Application Type Tested At Idle W/Vacuum psi (kg/cm2 ) At Idle W/O Vacuum psi (kg/cm2 )
Land Cruiser, LX450 31-37 (2.2-2.6) 38-44 (2.7-3.1)
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