What you need to do is this. Go to a parts store and ask them for a hand pump to pressure test your cooling system. Take the car home and allow it to cool down. Once the engine is cold, remove the radiator cap and install the hand held pump from the parts store and pressurize the system. Then you can check for leaks. NOTE: There is a heater core in the vehicle that can leak too. If you can't find the leak, then purchase a dye for cooling systems. Follow the directions and drive the car. Under a black light, the dye will glow from the leak.
Please keep in mind that the over flow may have been a little low just because when the system was filled, there could have been air pockets that escape when you drive the car. As a result, the system draws from the over flow. Refill it and then check it after driving it again to see if it continues to go low. If it does, then I would say there is a leak or other issue.
Saturday, September 10th, 2011 AT 2:54 AM