You pull out of your parking spot leaving behind an unknown mystery fluid, and now you’re wondering:

Is it serious?
Can I keep driving?
Do I need to refill something?
Should I call a mechanic?
Will it be expensive to fix?

Without knowing exactly what kind of leak you are dealing with, it can be difficult to know the answer to these questions. Fortunately, there are some clues that can help you decipher your mystery fluid leak.

While we certainly encourage you to always get your vehicle inspected if you suspect that it is not functioning properly, the following signs can help you diagnose your leak to help determine what you should do next.

Take a Closer Look

The color of your fluid leak is often a great indicator of the underlying problem with your vehicle. Dab the puddle with a paper towel to inspect the color of your leak, and then look at the lists below for possible culprits.

Brown/Black: Motor Oil, Brake Fluid, Gear Lubricant, Gasoline
Green: Antifreeze
Blue: Windshield Wiper Fluid
Pink: Power Steering Fluid, Transmission Fluid, Antifreeze
Yellow: Antifreeze (Radiator Coolant)
Orange: Rust mixed with Antifreeze or Water, Transmission Fluid
Red: Power Steering Fluid or Transmission Fluid

And last, but not least.

Clear: Never fear! This is usually just condensation from your A/C system.

Give it a Whiff

Some fluids have a distinct smell that might just be a dead giveaway. For instance, we all probably can identify the smell of gasoline from filling up our vehicles at the pump. If the leak has that distinct gasoline smell, then that’s probably what it is. Some fluids, on the other hand, are odorless, like transmission fluid. So if there’s no smell at all - that could be a clue as well. Here’s a breakdown of some of the smells you might encounter. Just be careful not to take too big of a whiff!

Gas smell: Gasoline (Obvious, right?)
Candy smell: Antifreeze
Burnt, Sweet smell: Power Steering Fluid
Fishy smell: Brake Fluid
Cleaner smell: Windshield Wiper Fluid
Cooking Oil smell: Motor Oil
Petroleum smell: Transmission Fluid
Odorless: Transmission Fluid, Water

Feel it Out

The thickness or the stickiness of a fluid can also give you some insight into your mystery leak. (Just make sure to wash your hands thoroughly after handling!)

Thick / Sticky: Antifreeze
Slick / Oily: Motor Oil, Brake Fluid, Transmission Fluid, Power Steering Fluid
Thin / Watery: Windshield Wiper Fluid, Water, Gasoline

Solving the Mystery

So, do you have it figured out yet?

Even if you think you have it figured out it’s always best to double-check with a professional mechanic, but knowing that your leak is likely just water or windshield wiper fluid - as opposed to something critical like brake fluid - can go a long way in providing peace of mind.