That's because I know the companies selling these things only want to take me for a ride.
Over the years, the Environmental Protection Agency has tested more than 100 "alleged gas-saving" products, aftermarket fuel additives and devices, including: the Auto-Miser, FuelXpander, Gas Meiser, Platinum Gasaver, Powerfuel, Ram-Jet, Star Gas Fuel additive, and Turbocarb, just to name a few.
In all of this testing, the EPA says it "has not found any product that significantly improves mileage."
In fact, the EPA warns, "some 'gas-saving' products may damage a car's engine or cause substantial increases in exhaust emissions." They could also void your car's warranty.
If you really want to squeeze more miles out of every gallon of gas, make sure your tires are properly inflated, change your air filter if it's dirty, combine trips, and skip the jackrabbit starts and stops.
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