2582288 - 1080D CRANKCASE VAPOUR/GAS RECIRCULATION SYSTEM

The evaporation emission control system prevents fuel vapours emerging into the atmosphere from the tank.Fuel vapours from the tank are conveyed through this system into an active carbon container, where they are absorbed.When the engine is running, a controlled intake of environmental air regenerates the active carbon. Fuel vapours are thus extracted and directed to the engine as a result of a command from the engine control unit.The system controls crankcase emissions of vent gases consisting of mixtures of air, fuel vapours and burnt gases that leak through the piston rings and also lubricant oil vapours by redirecting them back to the engine so they can be burnt.

Blowby gases from the crankcase rise to the cylinder head and are conveyed to two different intakes:

• with medium-high accelerator throttle openings, the gases are taken in through the port immediately downstream from the air cleaner (1).
• with small throttle openings (particularly when the engine is idling or in over-run), gases are taken in downstream of the throttle (2).