EVAP System Function Test
WARNING: This page is about a different car, the 2022 Audi RS 6 Avant and 2021 Audi RS 6 Avant. However, it is still accessible from the selected car via links, so may be relevant.
Vehicles with High-Voltage System
- In electric driving mode, the Solenoid Valve -N94- -2- closes the breather line -4- to the EVAP canister -3-, so that it is not overfilled with fuel vapor, for example, when driving electrically for days on end.
- Because the pressure in the fuel tank -1- increases due to temperature effects when the breather line is closed, the Fuel Tank Pressure and Temperature Sensor -GX49- -5- monitors the tank internal pressure and via the engine control module causes the Solenoid Valve 7 -N94- to open at a residual pressure of 0.3 bar (4.35 psi). Additionally, the valve opens when the fuel filler door release button is pressed, so that no fuel can squirt out of the filler neck when opening the cap to fuel.