We’ve all been there. You reverse out of your garage in the morning and notice a puddle of fluid sitting underneath your car. If you’re not super familiar with cars, their engines, or mechanical repairs, it can be pretty alarming. Especially if you’re noticing the puddle is growing in size.
So, how do you know when it’s time to take your car to the mechanic? How do you work out what that fluid is?
How to identify and diagnose the leak underneath your car
It’s important to stay diligent with mechanical issues in your car, even if they aren’t necessarily an “issue” just yet.
Being able to notice and identify a small leak in your engine before it’s a big problem will save you car troubles and more importantly, money down the line.
So, how do you identify that leak once you’ve noticed a puddle on the garage floor?
If possible, park on a clean patch of pavement, or position a large piece of paper underneath your car, where the fluid is leaking.
Note: it’s important to use white, clean paper rather than something recycled like newspaper. These kinds of papers can change the colour of the fluid and skew your diagnosis.
Why is my car leaking: Different fluid leaks and what they mean
Once your car has leaked onto the paper, you’ll be able to see the colour of the fluid and get a better idea of what it might be.
You’ll have to touch and smell the fluid to get an idea of the texture and scent.
Engine Oil
Greasy texture, dark brown appearance, found under engine.
Oil leaks are pretty common in cars, but that doesn’t make them ‘normal’. Your car needs oil to run properly and keep your engine in good, working condition.
Oil leaks may be caused by issues like a worn oil gasket, an incorrectly fitted oil filter, a corroded oil line, or an incorrectly secured oil plug.
Water
Watery texture, clear appearance, typically found under the air conditioner.
The least offensive fluid to be leaking from your car is water. The reason we call this the least offensive is because it usually isn’t actually a leak.
Water “leaking” from your car is usually a result of using your air conditioner while you’re driving. The leaking water is just condensation.
Coolant
Watery and slippery texture, green, red or blue appearance, under engine.
Coolant is most typically a green fluid but can come in red or blue varieties as well. You’ll notice a slippery or sticky texture to the fluid.
A coolant leak isn’t the end of the world and it’s pretty common. Top up your coolant in the meantime and get it to a mechanic as soon as you can.
Note: coolant is really important for regulating your car engine’s temperature, so be sure not to leave these leaks unattended for too long.
Fuel
Clear, slightly yellowed appearance, smells like fuel. Found under engine or centre of vehicle.
It’s tricky to diagnose the cause of a fuel leak in your car because of how the fuel travels through your car.
You may find fuel leaking towards the front of your car (near the engine) meaning it may be leaking from the fuel pump.
If it’s leaking from the rear of the car, it may be your fuel tank itself.
It’s tricky to work out why your car is leaking fuel without taking a proper look over the car and engine, so we definitely recommend taking your car to the mechanic if you notice this leak.
Auto Transmission Fluid
Greasy texture, red or pink appearance, found under engine.
The appearance of your transmission fluid depends on its age. If the fluid has been recently replaced, it’ll have a pinkish appearance, whereas an older fluid will be a dark red, brown colour.
Either way, if you identify auto transmission fluid leaking from your car, you should get it checked out by a mechanic ASAP.
Your auto transmission fluid is so essential to protecting your transmission. It works both as a lubricant and a coolant to your transmission. Meaning that if it is leaking, you run the risk of either burning or grinding your transmission — which is a costly issue.
Note: some manual cars may use an auto transmission fluid, however most utilise a gear oil.
Power Steering Fluid
Oily texture, red, pink, or clear appearance, found towards the front under engine.
Power steering fluid is the key to a smooth driving experience. You can typically spot a leak in your power steering fluid when turning your steering wheel becomes more difficult to turn.
The biggest risk when it comes to this kind of leak is that the power steering fluid pump will become damaged. So it’s important to get it checked out sooner rather than later to avoid a costly pump repair.
Brake Fluid
Light oil texture (similar to a vegetable oil), typical clear appearance, sometimes slightly brown, found underneath front or back of car.
This is a really problematic leak to have in your car and one we’d recommend you absolutely get checked out ASAP. We’d recommend calling a mechanic before you even attempt to drive the car.
It may even need to be towed to a mechanic for your safety.
Brakes run on a hydraulic pressure system. Your brake fluid is what creates the pressure that allows your brakes to make your car come to a stop.
When to take your car to the mechanic
Want the short and fast advice? Here you go.
Engine Oil
Ensure your oil is topped up and keep your car’s preferred oil on hand until you can get to a mechanic. Make your next mechanic visit a priority.
Water
This is likely not an issue. If you drive your car a few times without the air conditioner turned on and still experience a consistent water leak, then we’d recommend visiting a mechanic.
Coolant
Ensure your coolant is topped up and visit a mechanic as soon as you can.
Fuel
Get your car to a mechanic ASAP.
Auto Transmission Fluid
Get it checked out sooner than later — this can cause expensive issues.
Power Steering Fluid
Get it checked out sooner than later — this can indicate or cause issues in your power steering fluid pump.
Brake Fluid
Get your car to a mechanic ASAP — call ahead and seek their advice on whether you should drive in or organise a tow truck.
—Still wondering why your car is leaking or think the leak definitely needs a mechanic’s eyes? You can visit our experienced mechanics at any of our five workshops: Woolloongabba, Newstead, Milton, Bulimba, or West End.