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:
Suspensions
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Snow tyres
Use snow tyres of the same size as the normal tyres provided with the car.
Fiat Dealership will be happy to provide advice concerning the most suitable
type of tyre for the customer’s requirements. ...
Service schedule
The scheduled service must be carried out every 20,000 km.
(*) Or every 4 years for very demanding use (cold climate, idling in city traffic,
dusty areas).
Or every 5 years, regardless from th ...