How to fix an exhaust smell in your car

If your leisurely drive is being disturbed by rancid smells of exhaust fumes reaching the car interior, you’ll want to get that fixed as soon as possible. Not only does it signal a problem with the car that might become something more serious, it’s also not very pleasant and may even affect the health of yourself or your passengers.

Scrap Car Comparison have put together a round-up of the various aromas that may escape from your vehicle’s exhaust and detailed what action you should take to stop your car from stinking up the place.

Exhaust fumes pumping out of a car tail pipe

What Do Exhaust Fumes Smell Like?

There are multiple different scents that can escape from your exhaust pipe, and none of them are especially satisfying. You may find that your car smells smokey, or you might get a whiff of petrol when you’re driving or when the car is idling. You could even find your senses assaulted by the smell of sulphur, very similar to rotten eggs.

These smells are all caused by a variety of issues with your car, so it’s important to correctly identify which problem your vehicle is actually suffering from. Here are the reasons why your car might be expelling certain nasty smells.

What Could Cause an Exhaust Smell In Your Car

Cars are complex and unpredictable, but with so many of them on the road, it’s natural that certain problems will arise more commonly across the board. While we can’t say with complete certainty why your car’s exhaust smells bad, we can show you the usual suspects that are most likely to be the root cause of your unpleasant issue.

  • Petrol Smell – Rich air/fuel ratio: To be clear, we’re not talking about a fuel leak here, so don’t worry about trailing that distilled black gold all over town. It might be worth a check to rule it out, but it’s more likely a problem involving some unburned fuel being dripped into the exhaust pipe. If your car smells of petrol and it seems to be coming from the exhaust, the root of this problem could be too much fuel, or not enough air, being added to the engine, with the car’s on-board systems not able to adjust accordingly. Another telltale sign comes in the form of black smoke plumes exiting your exhaust. Overlook this problem at your own risk, as it can cause damage to other areas of your car, including the catalytic converter. Read on to find out why you really don’t want that to happen…
  • Sulphur Smell – Broken/Damaged Catalytic Converter: If you’re not much of a petrolhead, you’ve probably only heard of catalytic converters from when they were specifically targeted by thieves in recent years. They’re actually very useful, not only for the car itself, but for the environment and you can be stopped by police for not having one. They filter the polluting hydrocarbons, carbon monoxide and nitrogen oxides and convert them into water vapour, leaving the remaining emissions less harmful (but still not helpful) to the environment. If you can smell rotten eggs coming from your car, it’s possible that your cat converter has failed in some way, perhaps through wear and tear or contamination from petrol.
  • Smokey Smell – Exhaust Leak: An exhaust leak is quite common and often caused by general, unavoidable wear and tear. It may have also been caused by debris on the road, like rocks or stones, that has been flicked off the road surface and cracked the pipe open. If the leak is behind the catalytic converter, you’ll notice a nasty smell coming from the car due to the emissions which have not yet been filtered. You will probably also hear a difference if the crack is before a silencer that’s on your car’s exhaust system. If the smell doesn’t catch your attention, a loud rattle or rumble should.

How to Fix an Exhaust Smell in Your Car

Once you’ve established the cause of the nasty smells finding their way into your car, it’s time to put a stop to them. Of course, not every problem is solved in the same way, but there is one thing you can do to get everything sorted out and leave you with complete peace of mind: Get your car serviced.

The two types of service – ‘interim’ and ‘full’ – offer different levels of meticulousness. A full service will give your car a thorough checking over, and includes every inspection that features on an interim service. However, both types of service are far more comprehensive than a basic, annual MoT.

A full service involves your trained mechanic of choice inspecting the car’s exhaust system, therefore being able to easily locate any cracks, leaks or breaks that might be causing fumes to reach your nose in the driver’s seat.

A service of either kind is not cheap, so if you don’t want to pay out for a full check, you could try to narrow down the problem yourself and ask a professional technician to see what they can find based on your own observations.

Or, if you would rather make money than spend it, and you think your car has run its course, consider selling your vehicle through Scrap Car Comparison. Our expert scrap buyers will collect your car from anywhere in the country at no extra cost to yourself, and we can find the best price for your car in just 30 seconds. So, don’t let that bad smell ruin your day. Clear the air and sell your car for scrap or salvage today.

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