You know we can't diagnose this over a computer. You need to look for where the coolant is leaking from. Add water to the radiator if necessary so you can search for the source of the leak. If the coolant runs out as fast as you can pour it in, you won't have any trouble finding the location of the leak. If it's much slower and takes days or weeks to leak out, consider adding a small bottle of dark purple dye, then search a day later with a lack light. The dye will show up as a bright yellow stain that you can follow back to the source. Be sure to check inside the tail pipe as well as on the engine and radiator.
Auto parts stores will have the dye, and those that rent or borrow tools will usually have a black light.
Monday, January 12th, 2015 AT 9:30 PM