Almost a decade ago, we belonged to a classic car club. In 2005, when the wonderfully intelligent folks in Washington DC decided to require that gasoline must be cut with ethanol, classic cars starting breaking down like crazy. About the same time I began to notice a loss of power and rough idling in my 2005 Mustang GT. Strange coincidence? Nope...Our mechanics found no problems... they basically told us that Ethanol sucks. To be more exact, Ethanol sucks energy out of your car by generating lots of water vapor that condenses and turns into water inside your engine as the engine cools down. This then leads to all sorts of bad things happening inside your engine including rough idle, corrosion, reduced power and a failure to easily start.Ethanol is really just a form of alcohol produced from distilling plant matter, and that alcohol picked up other decades-old particulates in the gas tanks and fuel lines of the classic cars... moving all that old junk to fuel filters and engines, causing them to clog and seize. Alcohol also breaks down plastics and many rubbers, including those used in gas and oil lines & hoses of most lawn equipment and many older vehicles. What a mess.Across the board, our club's mechanics recommended a two pronged attack on Ethanol's detrimental effects: (a) regular use of STA-BIL to remove moisture from the tank & line while stabilizing the Ethanol in the tank to minimize further moisture production; and (b) periodic application of a fuel system cleaner like SeaFoam or BG44K (our choice, which I have used every three or four months since).Our mechanic recommended using the marine version of STA-BIL in our cars, saying that it just seems to work that much better than the regular stuff (but you do pay a bit more for it). Sometimes the marine version is tough to find around here so we use the regular STA-Bil too. Since we have been using STA-BIL to remove moisture and BG44K to clean the system and enhance performance, both my Mustang and our 1930 Ford Model A seem to have run much smoother.Thankfully, the EPA has now recognized that data actually shows ethanol is not as environmentally friendly as ethanol advocates claimed it would be (surprise, surprise... look who made money on that scheme) and the EPA has cut back Ethanol requirements starting 2014. Even if the EPA gets rid of the Ethanol requirement, STA-BIL and BG44K have proven their worth to us and we will continue using them from now on.If you have something similar going on and you know it is not a mechanical issue, give this stuff a try. Totally recommended based on our experiences in the cars we have owned.Go for it.