Tank ventilation system
As a result of evaporation, a sufficiently large amount of fuel vapors may occur in the free volume of the tank, which, in conventional ventilation systems of the fuel tank of the Transporter T4 , enter the atmosphere.
In order to avoid this, a vapor recovery system with a filter filled with activated carbon is installed. Fuel vapors enter the activated charcoal tank through the hose and condense there.
The activated charcoal tank is located under the left fender in the wheel well. While driving, the outside air that enters the engine is partly passed through the activated charcoal tank.
Air picks up droplets of fuel that have settled on activated carbon and delivers them to the combustion chamber of the engine. A solenoid valve is located in the ventilation system pipeline, which regulates the amount of air passing through the tank. The valve is controlled by the microprocessor module of the fuel injection system. At the same time, the microprocessor module performs stepwise (discrete) operation of the valve depending on the number of revolutions, load and readings of the lambda probe. At full load, the valve is fully open. If the current supply is interrupted, the valve closes completely.
Replacing the fuel filter T4 . Removing the fuel pump T4 .