I tried that magnetic thingy deal on my truck...
Abosultley no change whatsoever...almost a complete hoax.
It does have reasoning behind the theory and in a scientificly designed fuel distribution system that could put the magnetic field directly on the fuel line for each cylinder immediatley prior to atomization, it might work.
But my truck doesnt have a system like that so I guess thats why it didnt work.
The only thing that you can do with them is sell them and make the profit margin and apply that money to options that can help mileage on your car, such as Marks chip.
95 E34 530I V2.37
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Those who make peaceful revolution impossible will make violent revolution inevitable.
John F. Kennedy