on the other hand, wouldn’t it be easier to just schedule a day trip to somewhere fun once in awhile rather than worry about postponing FMM for as long as possible? I feel the need to get some portillo’s hot dogs... road trip!!! Oh wait... COVID restrictionsIf, indeed, you don’t use any gas at all during the year, when the FMM is triggered, be sure to have a charge in the battery (so you can drive on battery power in PPR mode to the gas station) and then drive around with the engine running until you run out of gas (a small amount of gas remains in the lines when the computer shuts off the engine because the "tank is empty"). Then add new gas, so all the gas in the tank is new gas (and the next FMM is postponed for nearly one year). The more fresh gas you add, the less impact the old gas remaining in the fuel lines has on the start of the next FMM. If you fill the tank of a Gen 1 Volt (as I did twice), the next FMM will happen 363 days later. If you only add the minimum (~1.5 gallons, as our forum friend Ari_C did), the next FMM will happen in 318 days.
If you just add more gas to end the FMM quickly, but don’t empty the tank, you’re then merely diluting old gas if you don’t soon use it... for example, if the FMM is running and you have 2 gallons of 12-month-old gas in the tank, you can add 2 gallons of fresh gas to end the FMM... average age will now be 6 months... next FMM is triggered 6 months later, when 2 of the 4 gallons in the tank will then be 18 months old... add 4 gallons of fresh gas then to end the FMM, and when the next FMM starts in 6 months, 2 of those 8 gallons will be 24 months old...