How to Change Coolant in a Pontiac Grand Prix
- 1). Raise the hood of the Grand Prix and make sure that the engine has cooled completely. Open the cap on the radiator. Raise the front of the car with a jack. Place jack stands under the front of the car for support.
- 2). Place a bucket or drain pan under the drain plug on the radiator. Loosen the plug with a wrench. Wait while the coolant drains out of the radiator. Tighten the drain plug and remove the drain pan.
- 3). Raise the car enough to remove the jack stands. Lower the front end back to the ground.
- 4). Add a 50-50 mix of distilled water and anti-freeze to the radiator. Fill the radiator completely. Start the engine and let it run until it reaches the normal operating temperature. Turn on the heater controls inside the car.
- 5). Top off the coolant mixture in the radiator as the level drops. The air will purge from the cooling system during this process. Turn off the engine and allow it to cool before you replace the radiator cap.
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