I have a 3 gallon external gas tank for my outboard Merc that is still filled with gas mixture. What do I put in it for the winter to keep the gas good for next season? 50:1 mixture
If your car is relatively new it is not a good idea to run oil through it. The O2 sensors don't like that. Just treat it with Stabil, SeaFoam or any of the other fuel system treatments and use it next season.
depends on how old it is now. if its from last spring your wasting fuel treatment.
read the fine print, stabilizers treat fresh fuel not dead fuel.
and its only 3 gallons.