With petrol prices reaching stratospheric heights, charlatans are coming out the woodwork to market fuel-saving devices to desperate motorists. Don’t be scammed.

Years ago, when I ran a blog, I had a running battle with a gent who swore he ran his Nissan 1400 bakkie on nothing more than water. You too, he said, could save a fortune in fuel by buying his patent-pending water-injection system for your vehicle.

If cars could run on water, they would. They don’t. Ergo, they can’t.

Conspiracy theorists will argue that this belief is mere brainwashing by the evil nexus of the auto and oil industries, which would never do anything to threaten their precious fossil fuel sales.

With the sharp – indeed, catastrophic – rise of South Africa’s petrol price, the scammers are out in full force again, with advertisements that promise a magnetic widget will save you fuel, or an additive in the fuel tank will make your vehicle run more economically, or an electronic gadget will improve your car’s fuel consumption.

I have bad news for you. Short of buying electric or hydrogen-fuelled cars, both of which merely transfer the energy generation, and hence cost, from the vehicle to electric power plants, the only way to save fuel is to drive less or drive with a lighter foot.

You can save oodles of fuel by doing 100km/h on the highway, instead of 120km/h. You cannot save fuel by purchasing a fancy widget or a magic pill for your fuel tank.

If you could, the additive would already be in fuel, or the widget would already be on your car.

Fuel-economy standards

This is not an article of faith. It is not a claim about the goodwill of automakers or the oil industry. Vehicle manufacturers make cars as fuel efficient as possible simply because they have to meet fuel-efficiency standards in most of their major markets.

These fuel-economy targets become more rigorous, year after year. For every flagship SUV with a five-litre V8 a motor manufacturer wishes to produce, it must make its mid-range and lower-end cars correspondingly more fuel efficient.

In the European Union, light-duty vehicles reached a fuel efficiency of six litres per 100km in 2019, down from seven litres per 100km in 2005. This 14% improvement is a consequence largely of EU regulations limiting emissions of pollutants and carbon dioxide. However, as of this year, fuel efficiency itself must be reported to European regulators, and standards have been tightened up to reduce the scope for deception on the part of unscrupulous auto manufacturers such as Volkswagen.

In the United States, corporate average fuel efficiency (CAFE) standards were introduced in 1975. This spelled the end of the muscle car era, and roughly halved fuel consumption from 1975 levels to 8.5l/100km by 1985. The target for 2020 was 6.7l/100km. This year, the US Department of Transport announced a remarkably tough target of 4.8l/100km to be achieved by 2026, which is expected to improve fuel economy by between 8% and 10% per year.

If any car manufacturer could achieve these draconian targets by adding a cheap gadget to your fuel line, they would do so in a heartbeat.

If any of them could do so by recommending a particular fuel additive, they would either get fuel retailers to add the additive to their product, or your vehicle owner’s manual would strongly recommend that you purchase that additive with every tank of fuel.

Third parties

The reason these additives or widgets are invariably sold by third parties, rather than your car manufacturer, is that they do not work. Some are actively harmful, causing corrosion or other damage to the engine of your car.

There are gadgets on the market that plug into your on-board diagnostics port and claim to change your engine control unit to ‘detune’ your car, sacrificing performance for gains in fuel efficiency. This sounds convincing to people who have no expert knowledge of their vehicle or its engine management system.

For a start, this couldn’t be done with a one-size-fits-all device, since all cars are different.

More seriously, however, the computer-controlled engines of today are finely tuned for maximum efficiency. Reducing the engine’s efficiency will not only sap performance, but also reduce fuel economy, and likely cause increased wear on engine components.

Once again, if car manufacturers could tune engines to be more fuel efficient, they would certainly have done so on all but their sportiest models made for rich customers who don’t care about fuel consumption.

Here’s a short list of miracle gadgets, debunked. No, the rest of them don’t work, either.


The swindlers will come up with all sorts of explanations of why their product is different, and their product works, and their product shouldn’t be tarred with the same brush as all the other scams that don’t work. Some of these explanations might sound plausible to non-experts, because that’s how marketers roll.

Witness the magic ingredients with sciency names of skincare products, for example, or the pseudoscientific claims of alternative health products. (No, ‘quantum bioenergy’ does not exist.)

The fuel-saver scammers are no different. They prey on desperate people who lack technical nous, and are already in financial difficulty, to convince them to part with money they cannot afford to lose.

Don’t bother searching the internet to see if the particular device or additive you discovered on a WhatsApp group or Facebook ad actually does work.

The swindlers are adept at setting up supposedly independent websites that use authoritative-sounding language to debunk competing products but describe their own products as exceptions to the rule.

Don’t listen to their ‘testimonials’, either. Or their ‘studies’ or ‘laboratory experiments’.

Anything sold on the basis of testimonials instead of statistical evidence is almost certainly a scam. Testimonials usually cannot be independently verified, and if they can, they’re either cherry-picked outliers, or outright liars.

As for scientific claims, it is certain that they will not point to peer-reviewed studies in reputable journals. If they did, once again, the car makers would be all over the invention to meet increasingly rigorous fuel economy standards. That auto manufacturers themselves are not interested is evidence enough that the claim is bunk.

How to save on fuel

There are two ways to save on fuel. The first is to drive like a granny. Accelerate gently, drive smoothly, and keep below the speed limit, especially on highways. This can easily get you an extra 100km from a tank of petrol.

The other way, as Nicholas Woode-Smith eloquently argues in Business Day, is to convince the government that petrol is an essential good that influences everything from the transport expenses of the poor to the price of food, and that therefore – just like bread and milk in the supermarket – petrol should not be taxed in any way.

That could save South Africans up to R10 per litre at the pump, and all it would take on the part of government is to throw less money at BMWs and bespoke suits and ‘security upgrades’ and VIP protection and astronomical civil servant salaries and dodgy tenders for friends and family.

True, that is a lot to ask of our corrupt politicians, but it would have an enormously beneficial effect on prices, not only at the pump, but throughout the economy.

Don’t hold your breath, though. It won’t happen. Our rulers are too selfish and too ideologically blinkered to even consider such far-reaching reforms.

But grabbing at straws like miracle fuel-saving products is not the answer either. Save your money, and your car’s engine, and if you must travel, slow down, and enjoy the journey.

The views of the writer are not necessarily the views of the Daily Friend or the IRR

If you like what you have just read, support the Daily Friend

Image by Hands off my tags! Michael Gaida from Pixabay


Ivo Vegter is a freelance journalist, columnist and speaker who loves debunking myths and misconceptions, and addresses topics from the perspective of individual liberty and free markets.