Why Car Smells Gas When Starting [5 Solutions]

car smells like gas
Table of Contents
    Add a header to begin generating the table of contents

    If you recently filled your gas tank and you can smell gas when you start your car, it may take a little while for the smell of gas to go away.

    Most of the time, this smell shows up because you were at a gas station getting fuel. If you can smell gas every time you start your engine, though, then that’s usually a sign of a problem. 

    It is generally not safe to drive when you smell gas. Most of the time it is something small like a missing gas cap or a gas cap with a damaged seal. Most of the time, however, the smell of gas is an indicator of something seriously wrong with your vehicle.

    Such a potentially serious issue may be something you would want a professional to look at, but you can save yourself a lot of money if you can resolve the problem yourself.

    In this article, we will go through all the common reasons you might smell gas coming from your car. So, before you take your vehicle to an expensive mechanic, check out these common reasons this problem may be happening below.

    Why Do I Smell Gas When I Start My Car

    1.Gas Cap Issue

    The absolute very first thing you should check if you smell gas when you start your car is check your gas cap.

    There is a chance you simply forgot to put your gas cap back on after fueling up your vehicle. In this best-case-scenario, and depending on the design of the car, this could cause fuel fumes to end up in your vehicle.

    Also, even if you made sure to put your gas cap back on, you should still take a look at it. The seal on your gas cap can develop cracks and can break over time.

    So, there is a chance your gas cap is installed correctly, but it’s just worn out. If it is, then it will also cause you to smell gas when you start your car.

    2.Bad Fuel Pressure Regulator

    Another issue that may cause you to smell gas when you start your car is a failed pressure regulator. When your fuel pressure regulator fails, it can cause fuel to burn too lean (thin) or too rich (thick). 

    Burning more fuel than you need wastes gas and causes unburned fumes to build up in the exhaust stream.

    So, that could also be what you are smelling. Keep an eye on your gas mileage, and if you see a decrease in fuel efficiency that comes along with smelling gas when you start your car, a bad fuel pressure regulator could be the culprit.

    3.Fuel Pressure Regulator Problems 

    Issues that you may be having with your fuel pressure regulator could also be the reason you smell gas while you’re driving your car.

    When a fuel pressure regulator starts to go bad, it will change the engine’s air/fuel ratio and will cause it to either burn too much or too little fuel. When the fuel mixture is out of spec, it can cause your car to burn much more or much less gas.

    If your engine is running rich (burning too much gas), that will certainly increase the amount of unburned gas in the exhaust system.

    So, when there are more gas fumes coming out of your exhaust, the more gasoline fumes end up in the ventilation system. Not only will this make your car smell like gasoline, but it will also lead to lower fuel efficiency and reduced engine power.

    If you can smell gas while you are driving your car, that is a major problem that could have one or more causes.

    4.You May Have a Gas Leak

    Another reason why you can smell the scent of gas when you start up your car is a fuel leak. If you are wondering ‘When should I be concerned about the smell of gas?,’ the answer is now. 

    This is pretty much the worst-case-scenario. If you are leaking gas, it makes your car really dangerous and expensive to drive.

    You could have a puncture in either a fuel line or your fuel tank. This one is pretty easy to check. Just look under your vehicle and see if you can locate a puddle of gas under your vehicle. 

    WARNING: If you have a fuel leak, do not drive your car. In this case, you would need to have your vehicle towed to an auto repair shop if you cannot patch the leak yourself.

    The Danger Behind A Fuel Leak

    If you have a leak in your fuel system, that is a very dangerous issue that will definitely cause your car to smell like gasoline. A fuel leak is something that can happen at many different points in your gas system.

    There are a lot of connection points and fuel lines that run from the back of your car (the gas tank) all the way to the front of your vehicle (the engine). It could also be one of the many lines and/or fittings in between those two points.

    You will smell gas at different times depending on where exactly the gas leak is. If your leak is in the fuel injection system, for example, you will more than likely smell gas while driving and right after driving.

    In other cases, it could be something as simple as the vent hose leaking, which will cause gas vapor to leak out of your fuel system.

    Gas leaks are very dangerous. This is because gas can puddle under your car and could easily ignite. So, if you are thinking there is a gas leak in your system, you should fix that as soon as you can. 

    How to Fix Car Smelling Like Gas?

    If you are wondering, ‘Why do I smell fuel when I start my car?,’ then the first thing you should know is that the source of this problem could be one or more of many things.

    It could be something as simple as a loose or missing gas cap or something more serious like faulty or damaged fuel-system components in your vehicle. 

    If you are lucky then it’s just a faulty gas cap. That is a low cost part that is easy to replace. All you have to do is make sure you get the right kind of gas cap for your vehicle. After replacing the cap, check the fuel or cap for any faults the next few times you fill your tank.

    Should You Let A Professional Handle It?

    If it’s something more complicated than a punctured tank, you may have to take your vehicle to a professional.

    Changing a tank is a technical job that must be done correctly the first time. If you are confident in the repair or replacement of the fuel tank, however, you should at the very least drain the fuel from the tank before you start working on it.

    Also, make sure to jack up your vehicle properly. After that, crawl to the area where the leak is coming from.

    You will have to use epoxy to patch the tank. Make sure to sand the area first, and then use a rag and alcohol to clean the sanded area. Then, apply the mixed epoxy in and around the hole of your gas tank.

    Let the epoxy dry for a few minutes. Finally, fill up your tank and thoroughly check for leaks again.

    Addressing Fuel Lines Issue

    If the leak is in your fuel line, then it’s best to change the entire damaged fuel line rather than trying to patch or repair it. Replacing a fuel line involves jully jacking up your vehicle, disconnecting all of the fuel connections with a wrench.

    You will need a screwdriver, along with other basic hand tools. You will also need specific socket sizes for your vehicle. Make sure to inspect all of your fuel lines and fittings for any issues, not just the one with an obvious leak.

    Modern fuel systems rely on a charcoal canister. This charcoal canister helps protect the environment against unburnt fuel vapours. This canister is located under the hood of your vehicle. 

    If your canister is damaged, you will need to remove the canister connections from your vehicle with a wrench. After that, check the o-ring and rubber seal on both ends of the canister. If they are loose, then this may be your issue. Simply replace the seal.

    Remember to properly clear the connection areas of dirt and debris before replacing the seals. If this step is skipped, it can cause the seals to leak gas. If you replace the seals properly and this does not fix your issue, then you may need to also replace the canister itself.

    Car Smells Like Gas When I Start It But It Goes Away

    Why do I smell gas fumes when I start my car? If the smell of gas when starting your car, but that smell goes away when you start driving, then that means you more than likely have a gas leak somewhere in or around your vehicle.

    The fuel system in a car is very complex, so it 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?

    Usually it is not safe to drive when you smell gas. If you are lucky, it could be something benign like a missing gas cap, but in most cases, the smell of gas is an indicator of something seriously wrong.

    Keep in mind, breathing in gas fumes can make you sick, and can even kill you. So, don’t waste any time if you smell gas, check for leaks right away.

    Why Do I Smell Gas Outside Of My Car?

    This can be caused by a bad fuel pressure regulator. If your regulator goes bad, it can cause your engine to run either too lean or too rich. So, anyone who is standing near the vehicle will be able to smell gasoline vapors while the engine is running.

    Why Do I Smell Gas When I Turn On The AC In My Car?

    This is more than likely a gas Leak. If you smell gasoline every time you turn on your vehicle’s air conditioner, that usually means you have a gas leak somewhere under the hood and fuel vapors are being sucked into the air conditioner’s air intake.


    It is unsafe to drive when you smell gas coming from your vehicle. Hopefully you were able to resolve the issue by getting a new gas cap. 

    Remember, inhaling gas fumes regularly can make you sick or can even kill you. Also, the excessive release of fuel vapor is a sign of serious problems with your vehicle. So, we hope this article helped you get your problem resolved!

    While addressing the smell of gas in your car is important, don’t forget to tackle other car-related concerns such as removing deployed airbags, handling the delicate situation of repossessing a car from a family member, and fixing a sun visor that won’t stay closed. Staying vigilant and informed about these issues can help ensure a safe and comfortable driving experience.”

    Avatar of Keren Simanova

    Keren Simanova

    Welcome to my car seat blog! As a mom of 3, I put together with other hard-working moms a highly informative one-stop car seat resource, full with many reviews and buyer guides. I hope you find it invaluable. Thank you for trusting me & my team! - Keren
    Receive the latest news

    Subscribe To Our Weekly Newsletter

    Get notified about new articles

    Keren Simanova

    Welcome to my car seat blog! As a mom of 3, I put together with other hard-working moms a highly informative one-stop car seat resource, full with many reviews and buyer guides. I hope you find it invaluable. Thank you for trusting me & my team! - Keren