Ah, the nauseating smell of gas. That’s exactly what you want to smell on your way to work. Before you panic, there’s some good news. We’ve put together the top 10 reasons why your car smells like gas.
Follow along and try some of the troubleshooting and solutions that we’ve spelled out. Hopefully, we get you one step closer to a smell-free ride.
Why Does the Inside of My Car Smell Like Gas?
The smell of gas is so annoying and can be dangerous. There are a lot of different reasons why your car might smell like gas.
The short answer is that a part of your car is faulty. Unfortunately, there are dozens of parts that come in contact with fuel at some point.
Gasoline is the fuel that your car uses to drive. You pump in liquid gas and the engine does some magic to turn it into an explosive vapor. It uses controlled explosions to move your car and get you from point A to point B.
You might not care about how your car works, but this quick explanation will help you to understand where your problem is. Any step of this fuel-exploding process can have a problem. The gas vapor that should be turned into fuel is creeping out somewhere, and that’s why you smell gas inside your car.
Finding the problem area takes a little bit of troubleshooting. If you want to find the problem yourself, it will help save some time and money at the car shop. It might even save a trip altogether if the solution is easy enough.
Car Smells Like Gas When I Start It But it Goes Away
If you only smell gas when you first start your car, then you’re most likely dealing with a gas leak somewhere in or around your vehicle. This may be coming from the engine itself, the fuel line or the exhaust system where gas emissions evaporate.
Is it Safe to Keep Driving if I Smell Gas?
In most cases, no it isn’t. Some of the simpler problems won’t lead to your car exploding or catching fire, but there’s no way to tell how serious the problem is until you troubleshoot it.
Simply breathing in gas fumes can make you sick, and in extreme cases, it can kill you. It’s always best to check for a leak as soon as you possibly can, and get the car fixed immediately afterward.
Without further ado, let’s check out the top 10 reasons why your car smells like gas.
1. Loose Spark Plugs
If your spark plugs were never tightened to the right torque, they could have loosened over time. Perhaps your truck smells like gas because the sealing ring around the spark plugs aren’t seated properly.
In this case, the fumes will come out of your combustion chamber and go right into the air intake for the HVAC system of your car. In other words, the engine will spew gas fumes right into your air vents.
Your spark plugs will have washers on the threaded part that seal everything. If these washers are cracked, missing, or broken, then the gas smell could be coming from these guys.
Troubleshooting and Solution
Check the spark plugs and see if they look okay. If they do, carefully remove each one and remember where they go. Mixing them up when you re-install them will cause your car not to start. It might be easier to just remove one at a time and put it back after.
If everything looks okay aesthetically, let’s check out the torque. It’s not a problem if you don’t have a torque wrench. Just loosen the spark plugs until you can hand-tighten them.
Screw it in as hard as you can by hand. Grab your wrench and give it a quarter turn. Now you should be at the right torque.
At this point, you can repeat this step for all of your spark plugs. This will make sure that all of your plugs are seated at the right torque.
2. Faulty O-Ring or Gasket Around the Oil Cap
This might be one of the more common causes for the gas smell in car. Troubleshooting this takes less than a minute; you don’t even need to jack up your car.
The oil cap is, no surprise, the cap to your oil reservoir. This is the part that you take off when you change your oil. If it isn’t properly seated, oil and gas fumes will make their way out and into the atmosphere, resulting in a fuel smell in your car.
Troubleshooting and Solution
Pop the hood and locate the oil cap. It is typically black and has the word “OIL” on it, or a picture of an old-timey oil can.
Look around the cap. Is there a lot of dirt and oil stains below the cap? This is a clear sign that your cap isn’t sealed correctly.
Take off the cap and look at the O-ring on the underside of it. If it’s flattened, cracked, or missing altogether, it’s time for a replacement. Luckily your local auto part store will stock this part for a few dollars.
Finally, take a look at the cap itself. If the cap is cracked or busted, then you can just replace the whole piece. Make sure you find a cap that’s the right size for a replacement (they make a lot of different sizes depending on your car). If nothing else, check out the salvage yard and see if you can grab an oil cap.
If you smell gas when you start car, then it is most likely due to a missing or faulty oil cap.
Additional Comment
If your oil cap is missing, that is probably the reason why your car smells like gas. Replace it as soon as possible because a missing cap can lead to carbon monoxide poisoning and death.
If you just got an oil change and smell gas, pull over and make sure you have an oil cap.
3. An Oil Leak
The oil in your car is mixed with gas that hasn’t been burnt yet. This means that if you have an oil leak, that could explain the gas smell in your car.
In this case, the oil will have to hit a hot surface in order to burn the gas and create the smell.
Troubleshooting and Solution
Pop open the hood of your car. Use a flashlight and take a close look around. If you see any dark, wet, or oily spots on the engine itself, this could be oil.
You can also find an oil leak by checking under your car after it’s been parked overnight. If you notice a black spot underneath, it could be oil.
One of the biggest places that your oil can leak is your valve cover gaskets. These are at the top of the engine, right above the exhaust manifold. This area of your car produces a lot of heat, which means you would definitely smell gas if oil was leaking here.
You can also take a look under the hood when your car is running. If there’s smoking coming off the engine, that’s a good sign that there’s an oil leak.
The solution has to do with where your leak is coming from. You might wind up replacing a part, a gasket, an O-ring, or tightening an object. If you can’t find your leak, you might have to take your car to the shop.
4. Exhaust Fumes
Another part of your car that contains gas is your exhaust fumes. These fumes are the result of burning gas to accelerate your car, and they are supposed to get pumped out to the exhaust pipe and away from your car.
If you have an exhaust leak before your catalytic converter, you will notice a gas smell in car. The catalytic converter scrubs the exhaust and cleans the smell, so if you smell something, you know it has to be before that.
Troubleshooting and Solution
At least you know where to start looking. Troubleshooting this problem is a little harder for a DIY-er. If you have a good feel for what your car sounds like, you’ll notice a louder exhaust noise when you have an exhaust leak. Revving your engine will give you a better chance to hear the difference.
A leaky exhaust will also make a tapping noise while the car accelerates. The closer that the leak is to the engine, the louder the ticking noise.
Another way to troubleshoot this problem is to put a towel over the tailpipe. Hold the towel so that it clamps off the exit of the tailpipe. As the car idles, see if the towel builds up with pressure. If not, then you have a leak somewhere.
This is another problem that can’t be fixed on your own. A leaky tailpipe would have to be taken to a mechanic, but at least you know why your truck smells like gas!
5. Missing, Loose, or Faulty Gas Cap
Just like a missing or loose oil cap, your gas cap can also cause a gas smell. The big difference here is that you won’t have a gas smell in your car. You’ll only smell gas when you’re outside of your car or maybe if you’re idling with your windows down.
Troubleshooting and Solution
The first thing you can check is if your gas cap is even in. You might have forgotten to put it back on after filling up (or the gas station attendant if you live in a state that you don’t pump your own gas).
If there is a cap, give it a twist clockwise and make sure it’s tight. If it is fully tightened already, take it off and examine it.
If you notice that the O-ring is flat, broken, missing, or cracked then it’s time to replace your gas cap.
In some cars, your check engine light will come on if your gas cap isn’t fully tightened.
6. Exterior Gas Spill
You might have spilled gas on the exterior of your car. This doesn’t mean that there’s a gas leak anywhere, just that gas was splashed on your vehicle recently.
Troubleshooting and Solution
If you check everything else and can’t find a culprit, try to think back. Did you just recently fill up your car with gas? If so, roll the windows down and drive for a little bit.
If the smell still persists, then it wasn’t a gas spill.
If the spill occurred in your trunk or in your vehicle, then you need to act fast.
Use old towels to soak up as much of the gas as you can. Use a mixture of equal parts baking soda, hot water, and white vinegar and rub it in the area that you spilled. This will help to neutralize the odor.
Reach for your favorite odor killing spray and give it a spritz afterward.
7. You Have an Old Car
Cars built before the mid-'80s might smell like gas when you start them up and shut them off because of the technology they used in the carburetor and float bowl. On top of that, those older cars typically don’t have a robust evaporative-emissions system built in.
In this case, there’s nothing you or a mechanic can do to fix the problem. As long as the faint gas smell goes away after a few minutes, there’s nothing to worry about.
8. Poor Fuel Pressure
The fuel in your car’s system is constantly under pressure. This helps it to get where it needs to and keeps your car driving smoothly.
If you have poor fuel pressure, you’ll smell the result of your car burning too much fuel. The gas mixture in your car will either be too thin or rich since your pressure regulator isn’t working correctly.
Troubleshooting and Solution
If you have weaker power when you put the pedal down, that could be another sign.
If you find yourself filling up more often and your fuel efficiency goes down, that could be another sign. At any rate, this is a problem that can be fixed by your local mechanic.
9. A Gas Leak
If you have a gas leak, you will definitely notice a fuel smell in your car. It was mentioned earlier, but your car pumps gas from one end to the other. You can have a gas leak anywhere along this process.
Troubleshooting and Solution
The first indicator that you have a gas leak is that your fuel gauge is dipping much faster. If your fuel level goes down overnight, that’s a pretty clear sign that you have a fuel leak.
You can also idle your car for a little bit and see if you notice a multicolored puddle under your car. Checking your car after it sits overnight should also result in a puddle under the car if there’s a fuel leak.
The leak could be coming from your injector, fuel tank, fuel line, or injection line.
A way to tell if it’s a fuel leak versus a gas leak is to smell the mixture coming out. Oil spills will have a fainter smell of gas than a gas leak. Take your car to the shop and let them know that you have a gas leak.
10. Faulty Charcoal Canister
The last thing it might be is a faulty charcoal canister. This is another part of your evaporative-emissions control system in your car.
This canister is filled with charcoal, and fuel vapors are stored here before being sent to the engine to be burned.
Troubleshooting and Solution
A cracked canister lets the fuel vapors release, and you will probably be able to smell it from the inside of your car. If your check engine light is on, this could be a sign of a faulty charcoal canister.
If you hear a pinging sound, have reduced performance, or smell stronger emissions than usual, that could point to your charcoal canister.
The replacement is tricky, and you should take your car to your mechanic.
Now you know what to look for when you have a gas smell in your car. It’s a potentially dangerous situation, so definitely don’t drag your feet on this one. Try out the tips above and see if you can find the problem.
If the problem is too severe, take your car to a local mechanic.
Finding a Local Mechanic or Car Dealership in Kansas City
If you do decide that your car needs repairs from a trained professional and are seeking out a local mechanic, a great option is to go straight to a dealership for the kind of car you have. If you drive an Audi, you can take your car to Audi-Shawnee Mission where they will have all of the necessary parts and expertise of your particular vehicle.
If you would rather not deal with fixing your car and want to look for a newer model, you can talk to the sales experts at Audi-Shawnee Mission and trade in your old car so it's no longer your problem. Drive away in the perfect Audi for your needs and leave that old gas smell behind.