What to do if your car is leaking

You’re walking out to your car, coffee in one hand, keys in the other, and you spot it - that dreaded little puddle forming under your car. Great. Now you’re wondering if your beloved is crying or just sweating... Either way, you’re asking yourself: why is my car leaking? 

Here’s the 411 on what could be going on under there, and when you should worry (and when you can chill). 

Water Leak (usually no big deal)

Let’s start with the good news. If the liquid is clear and odourless, it’s probably just water from your air conditioning system doing its thing. Condensation builds up and drips off—completely normal, especially on warm days or after a long drive with the AC blasting. 

What to do: Nothing. Carry on. 

Oil Leak (now we’re talking) 

If the puddle is dark brown or black and feels slick, you might have an oil leak. Could be a worn gasket, a loose oil filter, or a cracked sump. Oil leaks don’t just stain your driveway—they can lead to engine damage if left too long. 

What to do: Get it checked. A quick stop at the garage could save your engine (and your bank account). 

Coolant Leak (often bright green, pink, or orange) 

Coolant/antifreeze leaks are common and usually come with a sweet-ish smell. Not something you want to ignore—coolant keeps your engine at the right temperature, and without it, things can overheat fast. 

What to do: Book it in. Don’t risk a cooked engine. 

Transmission Fluid (usually red or brown) 

This one’s important. A red or reddish-brown puddle could point to a transmission fluid leak. If you’re driving an automatic, this fluid is essential for gear shifting and general drivability. 

What to do: Don’t wait. This isn’t a “wait and see” situation—get it looked at pronto. 

Brake Fluid (clear to yellow, slippery, and dangerous) 

If your car is leaking brake fluid, you'll want to take that seriously. It affects your ability to stop, and, well... stopping is kind of important. 

What to do: Call for recovery. Do not drive the car until it’s sorted. 

Fuel Leak (smells like petrol or diesel) 

If you catch a whiff of fuel or see a shiny, rainbow-coloured puddle, that could be petrol or diesel leaking out. Apart from being a fire hazard, it's also costing you every time it drips. 

What to do: Step away from the matches, and have it fixed immediately. 

Rainwater Leaks (inside the car) 

If your car’s interior is soggy, the issue could be blocked sunroof drains, worn door seals, or even poor windscreen sealing. Not only is this annoying, but it can lead to mould and electrical issues. 

What to do: Have the seals checked out—and maybe put your car in some rice (joking). 

Cars leak. It’s not always the end of the world, but it’s never something you should ignore completely. A small drip today can be a big, expensive problem tomorrow. If you're not sure what’s coming out of your car or where it's coming from, that’s your cue to get it checked. 

At SERE Motors, we deal with leaks of all kinds (car-related, that is). If you’re in Belfast or Lisburn and spot something suspicious under your car, book in with our team and we’ll get to the bottom of it—no guesswork, no drama.