Description and function
WARNING: This page does not describe the selected car, but rather 17 other vehicles, including the 2009 Audi S4, 2009 Audi A4, 2008 Audi S4, 2008 Audi RS 4, and 2008 Audi A4. However, it is still accessible from the selected car via links, so may be relevant.
Only vehicles with automatic transmission are equipped with an electric vacuum pump. It is switched on by the engine control module, depending on intake manifold pressure.
The vacuum pump can be tested with On Board Diagnostic (OBD): any detected malfunctions are stored in the engine control module.
The engine must not be running when checking the function of the electrical vacuum pump via (OBD).