Usa models are equipped with an additional system with an evaporative emissions canister that prevents fuel fumes from being discharged into the atmosphere.
The breather hose (4) is connected to the canister filter (1); when the fuel has been filtered, it is returned through the hose (2) to the horizontal (a) and vertical (b) intake manifolds via the hoses (2a) and (2b). Drainage pipe (c) and the hose (5) vent to the ground.
For correct positioning of the connection hoses consult the indications given below.

Evaporative emissions canister
Removal of the evaporative emissions canisterOperating principle and characteristics of the ride-by-wire system
The engine control system of the diavel uses a ride-by-wire system with
motorised throttle valves. This eliminates all
direct connection with metal cables between the throttle grip and the throttle
valves themselves. Cables are used to
rotate the aps potentiometer, which generates an electric ...
Total distance covered indicator: "odometer"
This function shows the total distance covered by the vehicle
(in km or miles depending on the specific application).
At key-on the system automatically enters this function.
The odometer reading is stored permanently and cannot be
reset.
If the distance travelled exceeds 199999 km (or 19 ...
Refuelling
Never overfill the tank when refuelling. The fuel level should
always be below the rim of the filler recess.
Warning
Use low-lead fuel with 95 octane rating at origin
minimum (see "top-ups" table, page 173).
Check that no fuel is trapped in the filler cap recess.
...