No. Antifreeze is already colored. You'd have to add at least a gallon of something of a different color, and even then, what's the point? If you can see the food dye, you can see the coolant. The dye I'm referring to is for when the leak is so small the coolant evaporates too fast to leave a wet spot. The dye comes in a little bottle and is formulated to be used with the fluid that's leaking. It is dark purple, but when searching with a black light, it will show up bright yellow. Even though the coolant has evaporated, the dye will be left behind.
The dye is available at any auto parts store, and those that rent or borrow tools will usually have a black light, but this is an unnecessary expense for your leak if you're seeing wet spots on the ground. The wetness will lead you to the source of the leak just like the dye would.
Tuesday, July 14th, 2015 AT 11:07 PM