I have 2011 Aveo which leaks coolant at times. There are times a cup or 2 will leak out and other times I can go up to a week without any leaking or just a little bit will leak. At first it looked like it was coming out the drain plug on the drivers side of the car, I replaced that and it stopped leaking to begin with but now it's leaking again at times. Seem every time I can look at it stops leaking. It's driving me crazy. Any ideas?