A handy checklist for figuring out why your car smells like gas

why does my car smell like gas

You expect a gas station or the repair shop (or even a mechanic) to smell like gasoline, but not the inside of your car. If you smell gas while around or inside your vehicle, there could be a problem. Faulty parts, broken seals, and other issues could be the source of the smell. And yes – these problems do need to be dealt with as quickly as possible if you have any desire to keep your car from burning to the ground.

Unless, of course, you have roaches in your car. In that case, the best you can hope for is a raging inferno that takes 3 fire trucks to put out.

A list of all the common reasons why your car smells like gas

The following is a complete list of solutions for anyone who has ever asked “why does my car smell like gas?” Well…almost everyone. If your gas problem is human (or dog) related, this isn’t going to be of much help

1. Exposure to gas fumes

The simplest answer to this problem is that you just finished topping off your tank at the gas station. Lingering fumes from the station can get into your car when you exit for the pump and can remain for a short time after you reenter.

If you just refueled, wait five to ten minutes and see if the smell persists. If the scent is gone quickly, then your car has filtered out the gasoline fumes. If the smell hasn’t gone away, then you could have a different issue at play (and you need to keep reading).

2. You just refueled and spilled gas on yourself

Related to the previous issue, if you smell gasoline in the car, there’s a chance you spilled some on yourself or your clothes during the pumping process. Gasoline can soak into your clothes and cling to the skin like a mofo.

The smell of gasoline comes from the gas evaporating or turning from a liquid to a gas. If you spill a small amount of gasoline on yourself, that can be enough for the vapors to be detected. Wash your clothes / shoes when you get home, and scrub the spot with water and soap.

2012 Mustang GT smells like gas
This is my 2012 Mustang GT. I love it, but it smells like gas after a fill up sometimes. The smell was such as problem that I even made a video about it

3. The gas cap is loose (or missing)

If you haven’t spilled any gas (or been at a station lately), then you enter the realm of part failure being the issue. One possible issue is that you have a missing or loose gas cap for your fuel tank.

The cap on the fuel tank helps prevent gasoline from evaporating by trapping the vapors inside the tank, keeping more gasoline from evaporating. A missing or cracked cap would allow these vapors to escape and for more vapors to be created.

Inspect the fuel tank’s cap to make sure that it is present and not loose or cracked. Both of these failures would allow gas vapors to escape. If your gas cap is broken or loose, replace it as soon as you can.

4. You have a leaky fuel tank

Fuel tanks aren’t immune to degrading over time, just like any other car part. Things like rust and mechanical wear can create holes in your fuel tank, causing gas to spill and vapors to escape. Be sure to check your fuel gauge for any signs of quicker than normal fuel loss.

A visual inspection of the tank can reveal potential issues right away. Most leaky tanks will need to be replaced, although there are mechanics who specialize in gas tank repair. Heck – even the Goonzquad Brothers would opt to repair over replace. Personally, I’m a worry-wart, and I’d always recommend replacing the tank.

5. There is a leak in the fuel line

The fuel line is a rubber tube connecting the fuel tank to your engine. This connection is critical to getting fuel to the engine, and damage to this part of the car can be debilitating.

Inspecting the line for any cracks or tears is a good place to start to ensure that it isn’t the source of the smell. If it is, you must repair (or replace) it soon as possible. The fuel line usually passes by hot areas of the car (such as the exhaust), and any gas or vapor leaks can ignite the fuel. The resulting fire will be spectacular.

driving up to oil change garage
Pro tip: if you don’t know what a fuel line looks like (or you just refuse to get dirty), have the guys and gals at the local oil change place have a look.

6. You have a fuel pressure regulator issue

The pressure regulator for the fuel system ensures that the right mixture of fuel and vapor is mixed in the engine. If this regulator is faulty, the balance of fuel in the engine can get thrown off.

Since engines today are designed with specific fuel ratios in mind, an imbalance  can cause your engine to burn fuel inefficiently. It can also cause it to burn more fuel. Excess fuel consumption can create the smell of gas as the vapors build up faster and exit through your exhaust.

If your engine is stalling, and you see black smoke exit the exhaust pipe, the fuel regulator is likely to be your issue. A diagnostic test ran by a mechanic can check the fuel regulator to make sure that it is performing as it should.

7. There is a fuel injector issue

Injector issues aren’t all that common for fuel smell issues, but it does happen. The fuel injector has a rubber seal or O-ring that holds it in place. However, these seals can break or wear down over time, creating an escape for gas vapors.

An easy way to test this is to start up the car and then open the hood. If you smell gas, the smell could be coming from a broken seal on the injectors. They will need to be replaced.

8. The spark plugs may be loose or broken

Spark plug failure isn’t something many people think about, but they aren’t worth overlooking since they serve an essential role in the operation of your engine.

Spark plugs ignite the gas, allowing the combustion to drive the engine. If the seal around the spark plug breaks, then gas can leak out – and you’ll definitely smell it.

Carefully inspect your spark plugs, or have a mechanic look to see if your spark plugs are in good condition. The number of spark plugs inside your car will depend on your engine, but a failure in just one could be the source of your problem.

White Mustang GT
The only bad thing about owning an 8-cylinder Mustang is that I’ve got 8 spark plugs to stay on top of.

9. The oil cap gasket/O-ring is faulty

Another uncommon issue is the cap gasket or O-ring on your oil cap. A crack or other damage to these parts can allow gas vapors to leak through the engine and into the car’s cabin through your air conditioning vents.

If the smell seems like it’s coming from the AC, it’s worth checking under the hood and inspecting the area around the oil cap. If you find a lot of debris or build-up, there’s a good chance your cap gasket or O-ring is busted. These parts have to be replaced to stop the leak and remove the smell.

10. The charcoal canister is cracked

Many modern cars have a canister with charcoal scrubbers inside them that trap gas vapors in the EVAP (evaporative emissions control) system. These vapors get sent back to the engine to be burnt again as fuel. However, a cracked canister could be releasing these vapors into the air inside the cabin instead. That crack would create the smell of gas inside your car.

Since the canister connects to the electric system in your car, it has a sensor on it that reports on the canister’s status. Generally, an issue with the EVAP system will give you a check engine light on your dashboard. If you smell gas and get a warning light on your dashboard, it’s time to make a visit to your favorite mechanic.

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