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Fuel System Pressure Leak Down Test

  1. Release fuel pressure. See FUEL PRESSURE RELEASE  . Ensure area around fuel supply line and fuel rail are clean. Note direction of latch clip installation. Latch clip is located on top of fuel supply line at fuel rail. Using 2 screwdrivers, pry latch clip upward, and remove from fuel rail.
  2. Pull fuel supply line from fuel rail. Install appropriate adapter into fuel rail. See FUEL RAIL ADAPTER APPLICATION table below. Ensure adapter is fully seated in fuel rail. Install adapter latch clip into fuel rail, with latch clip fingers pointing downward. If latch clip will not fully seat so latch clip fingers extend downward below fitting on fuel rail, adapter may not be fully seated in fuel rail.
    FUEL RAIL ADAPTER APPLICATION

    Application Adapter No.
    2.5L 6539 Or 6631
  3. Connect fuel supply line to adapter. Ensure fuel supply line fully seats in adapter. Remove protective cap from adapter test port, and install a 0-60 psi (0-4.2 kg/cm2 ) fuel pressure gauge at test port.
  4. Start engine and allow to reach operating temperature. Shut engine off. Wait 5 minutes and check fuel pressure. Fuel pressure should not drop to less than 24 psi (1.7 kg/cm2 ). If pressure is not as specified, go to next step.
  5. Start engine and allow to reach operating temperature. Shut engine off. Clamp hose between fuel rail adapter and adapter test port. If pressure holds at or more than 24 psi (1.7 kg/cm2 ) for 5 minutes, repair leaking fuel injector(s). If pressure is not as specified, go to next step.
  6. Remove clamp from hose. Start engine and allow to reach operating temperature. Shut engine off. Clamp hose between fuel supply line and adapter test port. If pressure holds at or more than 24 psi (1.7 kg/cm2 ) for 5 minutes, check and repair leaking fuel lines or connections. If lines and connections are okay, replace fuel pump module.