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Fuel Delivery

WARNING: The fuel injection system is pressurized at up to 2.3-2.5 bar (34-37 psi). When engine is stationary pressure is maintained within the system. To prevent pressurized fuel escaping and to avoid personal injury, it is necessary to depressurize fuel system before any service operations are carried out. If vehicle has not been run there will be a small amount of residual pressure in fuel line. The depressurizing procedure must still be carried out before disconnecting any component within the fuel system. The spilling of fuel is unavoidable during this operation. Ensure that all necessary precautions are taken to prevent fire and explosion.

To check fuel pressure, first depressurize fuel system as follows:

  1. Remove fuel pump relay. Fuel pump relay is located beneath passenger seat. See Fig 1 . Start and run engine.
    Fig 1: Locating Fuel Pump Relay & Fan Control Module
    G00092708Courtesy of LAND ROVER NORTH AMERICA, INC.
  2. NOTE: Fuel at low pressure will remain in system. To remove low pressure fuel, place absorbent cloth around fuel pipe at the filter during disconnection.
  3. When sufficient fuel has been used to cause fuel line pressure to drop, injectors will become inoperative, resulting in engine stall. Switch off ignition. Disconnect the battery negative lead.
  4. Connect the pressure gauge on the outlet from the filter, located on the chassis under the right rear wheel arch. See Fig 2 .
    Fig 2: Identifying Fuel System Flow
    G00079868Courtesy of LAND ROVER NORTH AMERICA, INC.
  5. Reconnect the battery and turn the ignition to ON position, while observing pressure gauge. Pressure should be 2.39-2.67 kgf/cm2 . Maximum allowable pressure drop is 0.7 kgf/cm2 per minute.
  6. If pressure is low, ensure filter is not blocked and pump is operating correctly, recheck pressure. If pressure is still low replace pressure regulator. Repair or replace fuel pressure regulator as necessary. After completing the tests, retest the vehicle to ensure the faults have been rectified. If faults still persist, recheck using Lucas diagnostic equipment.