Stanadyne Fuel Additives are formulated to help restore your engine's maximum fuel economy, horsepower and torque. For regular maintenance, use Performance Formula All Season or Warm Weather Blend with every fill up and treat with Performance Formula Injector Cleaner 4 - 6 times per year. We also offer a cold weather additive, as well as a lubricity formula to use with very dry or winter blend fuels. Protect gasoline engines with Gasoline Additive+, to keep engine components clean, lubricated, and maintenance free.