Cars have fascinating ways of letting us know that they’re experiencing problems. Sometimes it’s an indicator flashing on the dashboard or unusual noise from the affected component. But smells are another way, and the smell of petrol is a perfect example.
A petrol smell in or around your car is never a good sign. Petrol is like the lifeblood of your car, and seeing or smelling it is a sign of a problem. If you’re smelling it, there might be a leaking fuel tank or a problem with the fuel cap. Besides that, damaged spark plugs, a leaking exhaust system, or an engine oil leak could be to blame.
This guide will help you troubleshoot the smell and determine where it originated, and more importantly, you’ll learn how to resolve the matter quickly.
Why Does My Car Smell of Petrol, and How Do I Fix It?
You must always take the smell of petrol seriously, whether you detect it inside or around your vehicle. While some of the possible causes are relatively minor, there’s always the possibility that it’s something more serious.
So, shut off your car as soon as you notice the smell and start troubleshooting for the following possibilities:
1. Leaking Fuel Tank
When you notice a petrol smell in or around your car, you must immediately check the fuel tank.
That doesn't mean it's a cause for panic, but this is the first potential cause you'll want to rule out as soon as possible.
The fuel tank is a solid container made from highly-durable materials. However, it’s located on the underside of your vehicle, typically towards its rear end.
Being on the underside means the tank is exposed to damage from the road underneath. Rocks and other hard items can hit the tank and cause a fuel leak, which causes the petrol smell that you notice when you’re standing around the car.
What to do: First, keep the engine off and ensure you’re parked safely. Then, identify and locate your car’s petrol tank so you can inspect it thoroughly.
If you find that the tank is leaking, you’ll want your car towed safely to your mechanic, who will likely recommend replacing the tank with a new one. Replacing a damaged fuel tank instead of just repairing it reduces the risk of fire or explosion.
Dealing with a leaking fuel tank is much more complex than just plugging the hole. To eliminate all risks, a total replacement by a trained technician is the best way forward.
2. Fuel Cap Issue
You might wonder, “What if my car smells like gas but isn't leaking?” Well, for starters, you can breathe a sigh of relief. Once you rule out a leaking tank, you can rest assured that you’re no longer in immediate danger.
Now, we can begin troubleshooting other potential reasons your car smells of petrol, like an issue with the fuel cap.
The purpose of your fuel cap is to seal the filler neck, preventing fumes from escaping the petrol tank and filtering dust, debris, and other contaminants that can get in the tank.
The fuel cap might be loose, like if you forgot to tighten it the last time you filled your car with petrol. However, it can also be broken or have cracks that cause fuel vapours to escape.
Those fuel vapours are why you smell petrol outside your car.
What to do: Firstly, check your fuel cap. The problem could be minor, such as a loose cap, in which case, you only need to tighten it.
However, if you find the cap cracked, broken, or damaged, you’ll need to replace it with a new one.
3. Spark Plug Problems
Suppose your car smells of petrol when you start it but not when it isn't running. In that case, the most likely issue is one or more of the spark plugs.
Remember what spark plugs do: They deliver the sparks needed to ignite the mixture of fuel and air inside the engine’s chambers. In other words, the spark plugs are directly exposed to the petrol you smell.
But what’s the connection?
Like the fuel cap earlier, one or more of the spark plugs might be loose. When that happens, fuel vapours can escape the engine and cause you to smell petrol when the car starts.
The same can also happen if the spark plugs are cracked or damaged. When that happens, the plugs fail to maintain a tight seal inside the engine’s chambers, causing the smell of petrol to escape.
What to do: Before you do anything, shut the engine off and let it cool down completely. The engine and the spark plugs run hot and could injure your fingers if you handle them too soon.
Then, remove each spark plug and inspect it closely. Next, you must replace damaged ones and tightly attach all your plugs.
4. Exhaust Leak
As you can already tell, it’s important to note where the petrol smell comes from and when it happens. For example, if a car smells of petrol outside, it could be due to a leak in the exhaust system.
More specifically, the leak is somewhere before the catalytic converter, which usually helps to remove odours from the exhaust gases. Instead, the leak causes untreated exhaust gases to leak out, causing the petrol odour you smell.
What to do: Your car will still drive usually despite the exhaust leak you have. However, you must immediately get your vehicle to your preferred workshop so they can sort the problem out.
Even though the car runs, it pollutes the air with harmful emissions if that gas escapes before going through the catalytic converter. So, you risk getting a fine or failing a technical inspection unless you resolve the problem.
5. Engine Oil Leak
Lastly, there’s also a chance the petrol smell comes from leaking engine oil instead. Engine oil sometimes has traces of petrol in it, and that could be what you’re smelling as the oil leaks in your engine bay and underneath the vehicle.
What to do: Once you rule out all the other possibilities and discover the issue is engine oil leak, you'll want to focus on resolving the root cause. An engine oil leak isn't good, but it's less dangerous than a petrol leak.
So, fix the leak and pour fresh oil into the engine, and you're good to go!
Help is hard to find, especially regarding car repairs. Thankfully, the Directory at CarpartAU makes it a lot more accessible. Use the Directory to find workshops in your local area and contact them directly for help with your car’s petrol smell or any other problem!
By Ray Hasbollah