All gasoline sold in the United States is required to contain effective detergent additives. Use of additional detergents or other additives is not needed under normal conditions and would result in additional cost. Therefore you should not have to add anything to the fuel.
See also:
Fluid Capacities
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Trip computer
General features
The “Trip computer” displays information (with ignition key at MAR, relating
to the operating status of the vehicle.
This function comprises the “General trip” concerning the comp ...
Water in diesel fuel filter
(Multijet versions - amber)
Turning the ignition key to MAR the warning light turns on, but it should go
off after few seconds. The warning light
turns on when there is water in the
diesel fue ...