Attention: Checking and adjustment can only be carried out when there is 4 liters of gasoline in the tank.
Empty the gas tank. To do this, pump the gasoline into canisters. Make sure that it does not spill over the edge of the canister.
Fill with 4 liters of gasoline.
Turn on the ignition for at least 2 minutes.
The pointer arrow should be on the first wide division of the red reserve zone.
Otherwise, remove the rubber plug from the quotation hole "A" and turn the adjusting pin with a 3 mm Allen key.
Note: If the rubber cap cannot be pulled out, the instrument panel and printed circuit board must be removed.
[This article was copied from an online resource: AUDIMANUAL]