Leakage Diagnostic Pump (LDP)

Leakage Diagnostic Pump (LDP) (USA vehicles)







The functional principle of the leakage diagnostic pump (LDP) is identical to that of the Cayenne vehicles. The complete fuel tank system is checked for possible leaks using the positive pressure method. This takes place only when the engine is running. The LDP is an electro-pneumatic diaphragm pump which is supplied via the intake manifold vacuum or vacuum pump on the turbo engine. Evaluation by means of a reed contact switch located on the diaphragm takes place after the pumping phase.













NOTE: The procedures for checking the fuel pressure, holding pressure and delivery rate of the electric fuel pump are described in the Technical Data.

Diagram of the fuel tank low-pressure side RLFS