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:
Fan speed adjustment
Proceed as follows:
❒ open completely central vents and side outlets;
❒ turn knob (A) to the blue sector;
❒ slider (B) at ;
❒ turn knob (C) to the required speed;
...
General failure indication
The warning light on the dial comes on when a failure is detected. ...
Changing the battery
If required, replace the battery with a genuine spare part having the same specifications.
If a battery with different specifications is fitted, the service intervals given
in the “Service schedule ...