a while after starting my car, the "add coolant" light comes on and a long beep with it. i've added coolant until it topped off, but it doesn't fix the problem. after driving for a while, it'll shut off, but it comes on again when i stop and start it up again. any ideas, anyone? its really annoying. should i flush my entire radiator?

 

The same thing happened to my friend. So I pulled the drain **** on the bottom of the radiator and let all the coolant out of the radiator. Then I took the thermostat housing off and ran a hose to the water pump and flushed that too(careful, the water form that will come out of the open drain **** on the radiator). Then I took the overflow off and dumped it. Put it all back together, put the hose in the top of the radiator and started the car and let the water pump circulate the water and flush it all out. After I did that I put the drain plug back in the Radiator, and filled it with a water/coolant mixture. The light and the siren have gone off and it worked. I think that it has something to do with really dirty coolant. Cause his **** was almost black. Good luck, and I hope it works for you.

Todd