Fuel saving electronic modules that plug into your car’s OBD2 port are widely advertised online, promising to boost your vehicle’s fuel efficiency. However, a recent laboratory test conducted by the German magazine “c’t” reveals a harsh truth: these so-called fuel savers are nothing more than blinking lights and empty promises. These devices, readily available in online marketplaces, are essentially fake and incapable of delivering any real fuel savings.
The test conclusively demonstrated that not a single one of the tested plug-in modules could actually communicate with the vehicle’s engine electronics. Instead, all they did was blink their LED lights, proving them to be nothing more than “factory-made electrical junk.”
To further deceive consumers into believing in the supposed fuel-saving effect, these scam devices employ several tricks.
One deceptive tactic is suggesting that the plug’s color is significant. Consumers are often prompted to select a “suitable” plug color when purchasing, with options like blue or red for diesel vehicles and green or yellow for gasoline cars. Some even claim color codes exist for gas vehicles. This color differentiation is completely meaningless and serves only as a superficial layer to add to the illusion of functionality.
Another fabricated feature found in most of these plug-in modules is a switch located inside the circuit board. Manufacturers’ instructions often dictate that this switch should be operated at specific times, usually requiring a thin object like a needle to access it through a tiny hole in the casing. Experts at “c’t” magazine dismiss this as “pure busywork to distract drivers.” At best, the button might alter the blinking pattern of the LEDs. This trick is likely intended to prevent buyers from quickly realizing the deception, or to make them blame themselves for the lack of fuel savings, perhaps thinking they didn’t press the button correctly or consistently.
Finally, to preemptively address any complaints from buyers, sellers often invoke the need for patience. They falsely claim that the automatic optimization of the vehicle’s electronics only takes effect after driving approximately 200 kilometers (around 124 miles). This fabricated “break-in” period is designed to discourage immediate skepticism and delay buyers from recognizing they’ve been scammed until after any return windows have closed.
The test’s conclusion is unequivocal: “As expected, simple OBD2 plug-in modules do not save fuel.” Even if there were potential to improve upon the engine control system, which is already optimized by the manufacturer for efficiency, it would require a far more sophisticated technical approach.
Moreover, any genuine modification to the engine control system would necessitate vehicle type approval. If these modules were actually capable of altering the engine control system, their use while driving would likely invalidate the vehicle’s operating license, leading to legal and insurance issues.
Don’t fall for the flashing lights and false promises. These OBD2 fuel saver gadgets are a scam and will not improve your fuel mileage. Focus on proven methods for fuel efficiency, such as regular vehicle maintenance and mindful driving habits, rather than relying on these deceptive devices.
