It’s been about three-and-a-half weeks now since I filled up a couple 5-gallon containers in anticipation of power outages during a winter storm. Since I’m a dumb dumb, I did not add stabilizer at the time, but I do have some Seafoam stabilizer on hand.
I understand fuel degrades over time and running degraded fuel can damage engine parts. Should I pour the fuel into my vehicle or will that gum up my car’s engine? Is it still worth adding stabilizer today so that I can continue to store it in my garage for a rainy day? The only other responsible alternative I can think of is taking it to a hazardous disposal site in my county. It’s octane rating 87, I believe it also has ethanol, in case that makes any difference.
Let’s say it is over a year old, what would happen if it’s used in a car?
It’d still probably be fine! First thing to go wrong is it picking up water, but that separates out in the bottom of the container, just don’t pour it in your car. If it was even older (like 2-3 years unstabilized) it’d start to smell bad (like thinner) and change colour a little (kinda yellowy). If you put that in your car, it’d miss occasionally unless you mixed it with some fresher gas like a bunch of people itt have suggested. More fresh stuff the worse it is. It’d dirty up your fuel system a little quicker too, but not enough to cause an immediate problem. The horror stories about old gas “gumming up” cars are from carburetor days and fuel aging in place in an open system, volatile bits evaporating away and remnants varnishing tiny holes in jets and slides closed
Please note that “gas” can be a lot of things worldwide that might act differently, this is a Best Coast take and still has to consider ethanol vs non. Ethanol fuel picks up water much quicker than non, I pretty much only use it in my car and only if I’m going to go through the tank relatively soon