What I recommend you do is pressurize the cooling system when the engine is cold and you can check closely for the leak. You will need a pressure tester. Most parts stores will lend or rent them to you. If you still can't find the leak when it is under pressure, a dye is made to add to the coolant. Once added, you will drive the vehicle or run the engine to circulate the dye and then check for leaks using a black light.
Let me know if you have other questions. NOTE: I am assuming that your leak is external and you see coolant on the ground. If that is not the case and coolant is being consumed, let me know.
Monday, December 30th, 2013 AT 5:31 PM