TDI Fuel Pump Priming: How to Bleed It (Articles)

The electric fuel pump can be activated in many Pump-Düse (PD) or Common-Rail (CR) TDIs using the selective actuator test. The diagnostic tool used in the Screenshot is VCDS.

Alternatively, it is often possible to control these functions via the engine control unit, using the basic settings (channel 35 or a similar function in the drop-down list).

The purpose of this procedure is to bleed the fuel system, for example, after installing a new diesel filter or performing repairs on the fuel injection system.