Prevent water and varnish from making spring a big headache.
Like a wine without a cork, gas can go bad when it sits around mingling with air. Fuel actually starts to turn nasty after 30 days. Since your car’s fuel system is not an airtight container, precautions have if it’s one that you tuck away for the winter. The easy solution is an additive called a fuel stabilizer.
What is this magic tonic stabilizing? It’s trying to prevent oxidation. Gasoline can form gummy deposits and layers of varnish that gunk up any part of the fuel system they can reach. Most gas contains some amount of ethanol, and that spells more trouble; ethanol is hygroscopic, meaning it attracts water from the atmosphere. Water and ethanol are corrosive, which is bad news for older tanks, fuel lines, and carburetors. Ethanol can also do nasty things to rubber seals.
A good stabilizer should prevent this badness for up to a year, and they’re beyond simple to use. The hardest part is remembering to do it.