Effective fuel management: fuel saving devices busted

Fuel management and saving money on the cost of fuel is paramount to every fleet management company so it would be understandable if Fleet Managers wanted to try fuel-saving devices. But how effective are these devices? Car and Driver researched the effectiveness of fuel saving devices and results are listed in this blog. Do fuel-saving devices work, or do the success of these devices depend on the cynicism of producers and the wishful thinking of consumers?

  • The Fuel Doctor FD-47 plugs into a cigarette-lighter socket and manufacturers claim that it increases the vehicle’s mileage through power conditioning of the vehicle’s electrical systems, enabling the electronic control unit (ECU), fuel injection and timing to work more effectively. According to Car and Driver, using the unit resulted in a very minor improvement that might have been explained by variables like wind.
  • Similarly, the Hot Inazma Eco, which claims to reduce the vehicle’s voltage and store electricity to provide a constant voltage to the electrical system, was judged by Car and Driver to have a negligible effect on fuel efficiency.
  • Car and Driver also dismissed the claims by producers of the Moletech Fuel Saver and the Fuel Boss Magnetic Fuel Saver to modify the properties of fuel and de-cluster fuel molecules for greater exposure to oxygen.
  • South African CAR magazine showed similar results in their study of fuel saving devices. They dismissed claims by manufacturers of the airflow modifier device that placing this device in the air intake pipe supplying air to the engine will result in fuel saving of up to 15%. According to its makers, using this device will help increase power output and reduce turbo lag because the improved airflow results in better fuel mixing. But CAR’s opinion is that the device in the intake system will restrict airflow and result in worse efficiency.
  • CAR also derided the claims of manufacturers of a fuel magnet that it would create a magnetic flux across the fuel pipe and change the molecular state of the hydrocarbon molecules and result in the creation of a charged state for easier vaporization and more complete combustion.
  • Claims that a fuel molecule enhancer dropped into the fuel tank would decrease the surface tension of the fuel, resulting in smaller droplets which have a greater surface area exposed to air combustion for better combustion and fuel efficiency results were also dismissed by CAR.
  • And finally, the claims that a fuel additive would boost combustion efficiency and raise the octane number of fuel for better fuel efficiency were, you guessed it, judged to be invalid by CAR.

Why do people recommend fuel saving devices?

CAR puts the positive reviews that can be found on product websites down to the placebo effect. CAR suggests that the only way for actually lowering fuel consumption is through driving smoother with less harsh acceleration and braking and lower speeds, eliminating excess mass and aerodynamic drag, keeping the engine in good condition through regular services, and inflating tyres to specification.

If you are looking for a proven method for saving money on fuel, check out Avis Fleet’s Intelligent Fuel Management. This unique fuel management system has helped many companies in a demonstrable way by analysing every fuel transaction in our bureau centre and helping them to avoid fuel fraud, theft and abuse.

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