Please choose the correct ending to complete the given sentence: Cars & Other Vehicles: [header] How to change a car radiator [title] Take off the radiator cap. [step] Only do this when the engine is cool. This will release pressure on the cooling system and prevent vacuum lock when draining.

Ending1: [title] Reduce pressure on the cold radiator by a quarter. [title] Remove radiator cover and drop coolant into hose already in place. Ending2: [substeps] After removing the radiator cap, let the engine cool. Slide off the radiator cap and use a screwdriver to rotate the radiator cap counterclockwise to unscrew it. Ending3: [title] Insert a fan to take the temperature. [step] The temperature slider on the side of the radiator should be set to 120 degrees fahrenheit (14 degrees celsius). Ending4: [title] Squeeze the radiator hoses. [step] If you feel a crunching sensation when you squeeze the hoses you probably have rust in the cooling system.

Answer format: ending1/ending2/ending3/ending4