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. Exhaust Gas Hazard
Carbon Monoxide Gas The engine exhaust from this vehicle contains carbon monoxide, a colorless, odorless, and highly toxic gas. As long as you properly maintain your vehicle, carbon monoxide gas will not get into the interior. Have the exhaust system inspected for leaks whenever The exhaus ...