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:
“Dualdrive” electric power steering system
The electric power steering only works when the ignition key is at MAR and the
engine is running. A new electrically controlled power steering system called “Dualdrive”
is fitted on the Fiat Pun ...
Automatic Transmission – If Equipped
The automatic transmission and differential assembly are contained within a single
housing.
The fluid level in the automatic transmission should be checked whenever the
vehicle is serviced. Opera ...
Low battery charge
Turning the key to MAR the warning light on the dial turns on, but it should
go out as soon as the engine is started (with the engine running at idle speed a
brief delay in going out is allowed) ...