A few days back I filled gasoline in my car from a gas station I don't use regularly. After a few minutes of driving the car from the gas station, I noticed that the engine felt heavier and there was a considerable amount of vibration in the engine as well. I suspect that the gas was bad and perhaps stale as well because very few customers purchase gas from that gas station. I drove only once after filling the gas from that gas station.
Should I replace all the gasoline by sucking out this gasoline and adding fresh gasoline from the gas station I use on a regular basis or should I just mix new gas with this bad gas? My car tank is almost full and only a few litres of fresh gas can be mixed with the bad gas. The gas available here is ethanol blended. Please suggest.