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:
To Resume Speed
To resume a previously set speed, push the RES (+) button and release. Resume
can be used at any speed above 20 mph (32 km/h). ...
Replacement Parts
Use of genuine parts for normal/scheduled maintenance and repairs is highly recommended
to ensure the designed performance. Damage or failures caused by the use of non-genuine
parts for maintenanc ...
Rubber hoses
As far as the brake system and fuel rubber hoses are concerned, carefully follow
the “Service schedule” in this section.
Indeed ozone, high temperatures and prolonged lack of fluid in the system ma ...