Honda Civic Service Manual: Engine Cooling

Engine

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Coolant Replacement (R18A9)

1. Radiator Cap 1. Wait until the engine is cool, then carefully remove the radiator cap. ...

See also:

Honda Civic Owners Manual. How to Refuel
Your fuel tank is not equipped with a fuel filler cap. You can insert the filler nozzle directly into the filler neck. The tank seals itself again when you pull out the filler nozzle. Stop your vehicle with the service station pump on the left side of the vehicle in the rear. &nb ...