After a while, coolant starts to accumulate foreign debris, in which case it can no longer do its job right. Coolant is one of the most important parts of the car, so you have to make sure your coolant is working at full capacity and that you know how to do a coolant flush.
Coolant should be drained completely and replaced about once every two years. Make sure you buy the right kind of coolant and properly dilute it with water to about 50/50 or at most 70 antifreeze/30 water. The car should be cool.
To flush the coolant system, just climb under your car, find the drain plug, slide a pan underneath it, and pull out the plug. Then, take the cap off the coolant under the hood so the fluid drains faster. Rinse with water to make sure any debris has been removed.
Once the system is totally drained, put the plug back in the bottom and pour the diluted coolant mixture into the reservoir so it’s about an inch below the neck. Turn the car on and let the coolant heat up, then add fluid until it meets the fill line. Put the radiator cap back on.