If you drive a car long enough, sooner or later you’ll probably see spots on the pavement underneath the car when you park it. Well, that could mean a lot of different things, but how do you determine what’s going on? Well of course one of the things you can do is to see where the leak is coming from. You know, is it coming from the front? It could be from the engine or radiator or any of a dozen different things, transmission and so on. Or is it coming from the rear which would be a differential or brake fluid or something like that.

Now, say you bring it to me in my repair shop, what am I going to do? Well I am going to use dye, I’m going to put it into the system that I think is leaking, then I’m going to use a black light like this one after we run the car for a few minutes, and we’re going to shine it in spots under the car that are wet. Here we can see the dye fluorescent, we follow that back to the source, and that tells us what’s wrong.

Now, you can buy these kits relatively inexpensively, they come with an inexpensive black light that works up to a point. You still may have to take it to a shop. 

Now, looking at where the leak is, that gives you diagnostic tools, looking at the color of the leak, well that gives you even more information. And that is if we see pink, that typically means that we have transmission fluid leaking. Dark brown, ugly looking stuff, that is going to be engine oil in most cases. Then we have power steering and brake fluid which can be clear or kind of a kinda grey-ish color. Then we have coolant. And coolant comes in a variety of colors. Pink and yellow and red and green and so on. Well, by looking at what is leaking, getting the color, to help identify it, where the leak is located, that can save you a lot of time in diagnosing. Whether you are doing it yourself or paying for it.

And if you have a question or a comment, drop me a line, right here at MotorWeek.