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 Service Manual. VIN, Engine, (Motor), Transmission Numbers, and Paint Codes ('13: Natural Gas models)
Vehicle Identification Number uxououm a. Manufacturer, Make, and Type of Vehicle ...