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Fuel Pump Check Valve Test: 2.8L

  1. Connect Pressure Gauge (VAG 1318) between fuel supply and fuel return lines in engine compartment. Ensure pressure gauge test valve is in OPEN position.
  2. Operate remote control switch for approximately 30 seconds. Move pressure gauge test valve to CLOSED position. Briefly operate remote control switch until maximum of 80 psi (5.5 bar) is indicated. Observe pressure drop on fuel pressure gauge.
  3. After 10 minutes, maximum allowable pressure drop is 7 psi (.5 bar). If pressure drop is more than allowable maximum, ensure no fuel leaks are present in fuel lines. If no fuel leaks are present in fuel lines, fuel pump check valve is defective. Replace fuel pump.