Busting the Myths: Why White Vinegar, and Baking Soda Don’t Really Fix Car Odours

We’ve been removing stubborn odours from cars for over 38 years, and in that time, we’ve seen it all. From coffee grounds to baking soda, and vinegar.

Most cars that come to us for professional odour removal have already been through the home remedy wringer. Even professional-grade products can fall short when the real problem lies deeper in the car’s fabrics, foam, and ventilation system.

"It didn't work as expected!"

The truth is, while these household hacks can certainly work, they are slow, inefficient and have their drawbacks. In many cases, they just mask it—or worse, make it harder to clean later. So before you reach for another home remedy, let’s break down why these common approaches don’t work as well as they promise and what truly does when it comes to getting your car fresh and odour-free for good.

1. Baking Soda - Bicarbonate of Soda

Why it's supposed to work

Baking soda is a mild alkaline compound. Many odours are acidic in nature, such as those produced by spoiled food or certain biological processes. When baking soda comes into contact with these acidic odour molecules, it can neutralize them through a chemical reaction, effectively reducing the odour. It can react with certain compounds to form new, less volatile compounds that do not have an odour. For example, when baking soda reacts with acids, it produces carbon dioxide gas and a salt, which can help eliminate the source of the odour.

In common with other substances on this list, it has a very complex - porous structure that allows it to adsorb various door-causing molecules. This means that the odour molecules adhere to the surface of the baking soda particles, which helps to remove them from the air or surfaces. It also absorbs moisture and will help prevent the growth of mould and bacteria that produce unpleasant smells.

The Science of Baking Soda - American Chemical Society
Can baking soda really absorb odors in the fridge? - McGill University
The Secret of Baking Soda - Davidson Institute

Why it wasn't effective

Of all the items on this list, baking soda is probably the most effective. If it hasn't been effective, it's probably because you were targeting the wrong areas. Baking soda is good on carpets and fabric upholstery; however, we find smells tend to come from hard surfaces such as glass and plastic. Tar from cigarettes or fats from pet fur do get into the air, then condensate on cold hard surfaces such as the inside of your windows. Aside from missing the target, baking soda isn't particularly efficient or quick - I once used baking soda to remove a musty smell from an antique leather box - it took several years! It can also be messy, difficult to remove again, especially if it gets damp.

A better alternative

Baking soda does work for fabric and upholstery, but there are products that work even better. Glade Shake'n'Vac or Astonish Shake and Fresh do the same thing, but do it better. They do contain baking soda and a whole lot more besides, and it's formulated to add a nice smell and be easy to remove. These products have been around since the 1970s, so they have had a long time to perfect a product that does a better job than just bicarbonate of soda.

Neutradol Carpet Deodoriser would be our recommendation because it contains deodorants, we have had lots of success with it. - "it contains over 50 ingredients which break down and eliminate bad odour molecules altogether."

So before raiding the baking section of Tescos, consider using something specifically designed for the job you want it to do. At the time of writing, Asda and Tescos are selling Neutradol for about £1 for 350g, while Baking Soda is £1.60 for 200g, so you'll even be saving money.

2. Activated Charcoal

Why it's supposed to work

Activated charcoal is created by treating carbon-rich materials (like coconut shells or coal) at high temperatures, which develops a vast network of microscopic pores.

Just 1 gram can have over 3,000m² of surface area—that's like the size of a football field packed into a pinch of powder! Like baking soda, activated charcoal works by Physical Adsorption (not Absorption) via Van der Waals Forces.

Odour-causing molecules (like VOCs (Volatile Organic Compounds), gases, or organic vapours) in the air stick to the charcoal's internal surfaces through weak Van der Waals forces—a process known as physisorption. This traps the odour molecules inside the charcoal's pores, effectively removing them from the air.

The basics of activated carbon adsorption - Watertech Online
Activated Carbon - Wikipedia
Activated carbon filters for the abatement of odours, VOCs and VICs - Tecnosida
Activated Carbon Technology Effectively Reduces Daily Odors - AZO Materials
What Does a Carbon Filter Do? - ISO-Aire
Critical review on the adsorption of taste and odor compounds by activated carbon - Chemical Engineering Journal

Why it wasn't effective

Activated Charcoal works best as a filter, such as on a gas mask, or an aquarium filter because air or water is being drawn through it. If you stuff it into a sock and just have it sitting there, there won't be enough air circulation to allow it to work quickly or efficiently. Whatever substance is in your car, which is causing the odour, can make bad odours, faster than can be absorbed. 

Additionally, Activated Charcoal doesn't kill bacteria, which account for many car odours. 

A Better Alternative

Finding a better alternative really depends on what you are trying to do. As a substance for filtering air, activated charcoal is great, provided you can pull the air through it, but if you want to get rid of your car odour, you need to get rid of it at source. So, Neutradol would be a better alternative.

If the air is damp and you have musty smells, then we would instead recommend a car dehumidifier pillow. These contain silica gel crystals absorb moisture and should absorb some of the smell too. In fact, it's rather similar to the silicate crystal cat litter, which also contains antibacterials and chemicals to absorb odour. Which is why you might be better stuffing this into a sock instead of activated carbon.  Or if you prefer something a little prettier, you can buy bags of silica gel scented beads from Airpure, which are specifically designed as car air fresheners. Just 75p. 

But, all this is just treating the symptoms. To remove odour, you have to remove the source. 

3. Dried Coffee Grounds

Why it's supposed to work

Most of the studies I can find into why coffee grounds work to remove odour, refer to carbonized coffee. In other words, they turned it into charcoal (see above).

Coffee grounds have a porous, carbon rich structure much like charcoal and are also slightly acidic, nitrogen-rich and good at adsorbing hydrogen sulphide which is a constituent in many bad odours.

They also smell of coffee.

Adsorption Characteristics of Volatile Organic Compounds on Used Coffee Grounds Based on the Breakthrough Curves - National Library of Medicine
Carbonized coffee grounds remove foul smells - Science Daily

Why it wasn't effective

It isn't going to be very effective for the same reason carbon isn't very effective. Unless you are pulling air through it, it can't efficiently remove the odours. 

And it's just treating the symptoms. To remove odour, you have to remove the source. Additionally, any coffee smell you may get, is masking the odour. 

As we live in a tea drinking nation, it isn't readily available to everyone. Most of us don't produce coffee grounds or a means to dry them. I doubt Mellow Birds instant coffee has the same qualities.

A better alternative?

If you have used dried coffee grounds, you have effectively made a Coffee Potpourri. It's organic material with complex structures, which contains natural oils and perfumes. It's Potpourri - you are likely to get similar results if you fill your ashtray with cedar wood shavings, allspice and dried rose petals. There's nothing wrong with this, but as odour removal specialists, it wouldn't be our go-to methods for dealing with problem smells. 

The same goes for orange peel, which is another thing we commonly see given as advice. 

4. White Vinegar

Why it's supposed to work

White vinegar contains acetic acid, which is thought to neutralize odours by reacting with certain alkaline odour molecules, such as ammonia. Acetic acid has mild antibacterial properties, which can kill some odour-causing microbes.

Why it wasn't effective

It wasn't effective because it's just acetic acid diluted in a lot of water. That's it. That's the trick. You may notice that I have been linking to scientific papers and articles by chemical engineers for all the other entries for further information as to how these substances work. I can't find any relevant studies for white vinegar. 

Leaving a bowl of it in your car will do next to nothing. Why would it?

Spraying it around your car may kill some bacteria on contact, but those dead bacteria will just become food for more bacteria. If you don't remove the source of the odour, the food on which bacteria thrives, the smell will return.

It should also be noticed that white vinegar will make your car stink of vinegar, and as it is an acid, it could cause staining on leather seats.

A better alternative

Practically anything is a better alternative to white vinegar. If you spray anything around your car, then get some Febreze - it has stuff in it that works!

Or should you prefer, dilute 1 part Zoflora to 40 parts water, and spray this. It's a powerful, but pleasant smelling disinfectant which will kill bacteria, and keep killing it for a while.  Although it will eventually wear off and if the source of the smell is still in the car, the odours will return.

To be fair to white vinegar, it is quite good at cleaning windows, and as we already mentioned, smells do adhere to hard surface such as glass. As it's an acid, white vinegar is good at cutting through oils and fats, and fully evaporates to leave your windows streak-free.

However, any cleaning product you buy from the supermarket, even the cheapest own-brand versions, will do a better job than white vinegar and have the advantage of not stinking of vinegar. 

Mixing White Vinegar and Baking Soda

You will often hear on Life Hack videos, that if you mix white vinegar and baking soda, it makes a great drain cleaner, or it can remove the smell of pet urine from your carpets... which is interesting. Assuming it's true that it's a great drain cleaner, I wouldn't want to put a drain cleaner on my carpets!

Truth is, it's neither. Vinegar is an acid, Baking Soda is an alkaline, if you mix the two together, you get a chemical reaction with lots of fizz and bubbles. The detergent companies have trained us to believe that bubbles (which are just air) make things clean. If you are pre-mixing the two into a spray bottle to treat pet urine odours, then by the time you spray it, the chemical reaction has already happened and cancelled each other out, creating sodium and water -- salt water.

While brine does help suppress the growth of bacteria, practically any product designed to combat pet urine problems will be more effective. The one we like is Chemspec Urine Contamination Treatment. 

5. Essential Oils

We recommend you avoid essential oils!

Aside from the fact that our aim is to remove odours, not mask them, essential oils can come with problems. 

For many years, we have been aware that air fresheners which contain essential oils can damage plastics. Keep in mind that everything in your car is a plastic or polymer, including the seats and carpets. 

We are also aware that because they are highly concentrate Volatile Organic Compounds, they can cause health problems.  It is now becoming better known that air fresheners can cause serious health problems for cats and dogs, but some people can be sensitive too, especially to tee tree oil, eucalyptus oil, and peppermint oil, which are the ones most often recommended masking the smell of mould and pets. These oils can cause an instant and serious allergic reaction in some people. 

6. Odour Bombs

Why it's supposed to work

It has to be made clear from the outset, that not all odour bombs are made equal. Some may just contain an odour like cherry (cherry bomb), some may be a disinfectant, many will contain a combination of both. What is important here is the method of delivery. 

The aerosol goes off for about a minute to ninety seconds, filling your car with a mist. In theory, that mist gets everywhere, through the air vents, under the seats and dashboard, and can, essentially, reach problem areas you can't reach.

Why it wasn't effective

If an odour bomb wasn't effective, it's because, as I keep repeating, you can't remove bad odours unless you remove the source of the bad odour. An odour bomb won't do that!

We have used odour bombs to great effect. During the pandemic, we used ones that put out a disinfectant, which testing by Autosmart International found to be highly effective. However, we generally don't use bombs because we use wet foggers and dry foggers instead. These are machines which put out a much higher volume of fog and allow us to run a variety of very specialized products through them. We fog all cars we work on to remove odour because it's a highly effective method, but we generally do this at the beginning of the job, to disinfect a car so it's safer to work on, and after we have cleaned everything and extracted the source of the smell.

We may have to dismantle or remove parts of the car to do a proper odour decontamination, but even so there are parts of the interior we can't reach, which is where a fogger comes in. 

The bottom line is, you can't just throw one of these in your car and expect it to remove bad odours permanently. You have to put in the work - then use the odour bomb. 

How to Remove Pet, Smoke, or Damp Odours from Your Car

The most common odour complaints in cars are usually from dogs and cigarette smoke, followed by the musty smell of damp.

The first thing to recognise is that the source of these smells isn’t just in one place—it’s everywhere. Cigarette ash, dog hair, and dander spread throughout the entire car. Hard surfaces collect tar, oils, and skin residues (sebum and lanolin), which feed bacteria and trap odours.

We’ve all seen the dust build-up on the dashboard and wondered how the inside of the windows gets so grimy. That grime and dust are a breeding ground for smelly bacteria and organic residue.

Step 1: Vacuum Thoroughly

Start by giving the car a thorough vacuum. Don’t just focus on carpets—vacuum everything, including the dashboard. A brush attachment helps to dislodge dust from crevices, but a detail brush works well too.

Lift up the rear seats and, if you’ve had dogs in the car, pull back the carpet to vacuum underneath. Don’t forget to vacuum the headlining as well—this area often gets overlooked, but it can trap a lot of dust and odours.

If dog smells are the problem, it’s crucial to remove all the dog hair. A rubber brush can help with this as it grabs and lifts hair more effectively than a standard vacuum.

Step 2: Apply Neutradol

Sprinkle Neutradol Carpet Deodorizer over all carpets and upholstery. Pop some in door pockets and other storage areas too. Leave it overnight, then vacuum it up thoroughly the next day.

Step 3 (Optional): Use a Wet Vac or Carpet Shampoo Machine

If you have a wet vac or carpet shampoo machine, use it now. We don’t start with it because adding water too early can spread the source of odours deeper into the carpets. Avoid wet-cleaning the headlining, as it’s often delicate and can be damaged by too much moisture.

Step 4: Wash the Interior

Now it’s time to wash all the hard surfaces.

• Warm Soapy Water: Fill a bucket with warm soapy water and use a large, good-quality microfibre cloth. Wring the cloth so it’s damp (not dripping) to avoid soaking the interior.
• Hard Surfaces First: Start by wiping down all the hard surfaces. Rinse and wring the cloth frequently to ensure you’re lifting away grime, not just moving it around.
• Use Household Cleaners Carefully: If you use a spray cleaner, spray it onto the cloth—not directly on switches or sensitive areas—to avoid damaging electronics.

Next, clean the headlining with a lightly dampened microfibre cloth. The cloth should be new or very clean to ensure it grabs dirt effectively.

Clean the Seat Belts Thoroughly: Seat belts are often overlooked, but they gather a lot of grime from your hands. They’re robust, so you can use a bit more water and even a soft brush to scrub them.

Finally, if you didn’t use a shampoo machine, give the seats and carpet a good wipe down and towel-dry them.

Step 5: Second Round of Neutradol

Once the interior is completely dry, sprinkle Neutradol again. All that cleaning will have dislodged more odour-causing substances, and a second application will help to absorb them.

Step 6: Final Touches

• Fabrics: Use a product like Febreze to freshen the seats and carpets.
• Hard Surfaces: Wipe them down with a disinfectant like Zoflora for added odour control.
• Odour Bomb: For those hard-to-reach areas (like vents and deep crevices), use an odour bomb or fogger to treat the entire cabin.

Step 7: The Ultimate Test

Now that you’ve done everything, it’s time for a final check. Here’s a tip:

Find someone with a keen sense of smell—ideally a young woman! Studies show that women generally have a better sense of smell than men, and younger women in particular have the sharpest sense of scent.

Ask her to take a fresh sniff of your car. If there’s still a lingering smell, she’ll pick it up right away—giving you the final clue on whether more work is needed.

A note on hypersensitivity
If your car has had an odour problem for a while, there is a chance that you have become overly sensitive to that smell. It is more likely to happen to the ladies, but it could be the case that you have reduced the odour in your car to such an extent that nobody else can smell it, but your nose can detect even the slightest trait. Unfortunately, there is very little that can be done about this. You can learn to live with it, or sell the car. If you do decide to sell the car, your efforts aren't wasted, as you'll get more for it now that the smell has been reduced.

Our top 7 list of top odour killing products, that actually work!

None of these products is a magic bullet to resolve your odour problems. But with enough prior cleaning, and used in combination, they can get the job done.  Most can be found in your local supermarket, the rest can be found online. 

Neutradol Super Fresh Carpet Deodorizer

It's much like baking soda, you use it in the same way, but it's far better. Neutradol Super Fresh Carpet Deodoriser is a powdered carpet deodoriser designed to neutralize odours and leave a fresh, clean scent. Unlike air fresheners that simply mask smells, Neutradol’s formula destroys odour molecules to leave your home smelling genuinely fresh.

Febreze Auto Fabric Refresher Spray

Febreze Spray is a popular odour eliminator that doesn’t just mask smells — it actively tackles them. It uses cyclodextrins, sugar-derived molecules that trap and lock in odour particles, removing them from the air. Combined with light fragrances, Febreze leaves a fresh, clean scent behind. We don't know how this car version of the product differs from the normal one, but we're confident it will do the job.

Zoflora

This is a concentrated disinfectant that kills 99.9% of germs with a range of pleasant smells. It's been housewife's choice for over a hundred years and is still going strong because it works. We recommend you add a capful to a bucket of water and use it clean hard surfaces. You can also put it in a spray to freshen up your carpet's and upholstery. (Use caution when using on leather. 

Microban 24hr Multipurpose Cleaner

Microban is a company that specializes in antibacterial coatings for just about everything - from chef's chopping boards, to hospital flooring, to hotel linen. They also do a range of antibacterial cleaners and sprays. It's a little more expensive than Zoflora, but it's jolly good stuff. 

Chemspec Urine Contamination Treatment

When our staff were professionally trained on all aspects of decontamination and odour removal, we were trained on Chemspec products.  We've never had any reason to change. This is the product we use for removing pet urine smells, and we swear by it. It works by breaking down urine crystals and preventing staining, as well as eliminating odours. This is a solvent-based cleaner that utilizes an anionic aldehyde solvent system for effective odour neutralization.

Dehumidifier Pillow

If you think you have a leak in your car, then you need to get it fixed as there may be gallons of water under your carpets! But if your car is damp because you do short journeys with wet kids on rainy days, these pillows are just the job. They will keep humidity down and prevent that fusky damp smell. These are rebranded and sold under lots of different names, but they are all pretty much the same, any will do. 

AutoSmart Bio Fogger Odour Bomb

Not all odour bombs are made equal, and we wouldn't trust some of them not to just put a smell in your car that masks odour, but AutoSmart Bio Fogger is a professional product that will fill your car with a disinfectant mist that can get to all those places you can't reach.
There is a right war and a wrong way to do it, just follow the instructions on the can.

Conclusion

Removing odours is hard. I recently saw a conversation between some car detailers where they said it's impossible to remove smoke odours. It's not impossible, but it is hard work. So why start out handicapping yourself with home remedies which either don't work, or aren't nearly as effective as commonly available, cheap household products?