5+ years, 3 Volt's and 1st FMM - Rat's

BAZINGA said:

Observation: I know the door label shows my car was built 06/16, but since the FMM chose today to run, can I assume my car was "built" or given birth on June 22nd 2016, 365 days ago? I say that because there must be a clock/calendar built into the car and someone had to write the code to make this work and it makes sense to say "365 days from TODAY start FMM on the day the car registered fuel being added". Thoughts/comments.

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The FMM is triggered when the "average age" of the gas in the tank is ~12 months old, which suggests someone filled your Volt’s gas tank about June 22, 2016.

The FMM continues until something happens to change that average age of the gas in the Volt. Until then, you won’t be driving in Electric Mode, even with a full charge. If you drive until you run out of gas, you regain access to the battery, but go into Reduced Propulsion mode (reminding you that out of gas means engine is no longer available).

Whenever you run out of gas, after you put new gas into the tank, the engine will start and run a short self-test. If all is ok, everything returns to normal and you continue on in the driving mode you choose. I once used the Torque Pro app to monitor my gas volume when parked on a level surface, and refilled when it read 0%, 0.0 gallons remaining. There was no engine self-test performed in this case, indicating more fuel was remaining in the lines than if I had driven until the ICE stopped for lack of gas.

Even if you run out of gas, there’s still a wee bit of fuel in the lines. When I ran out of gas in my 2012 Volt to end my first FMM and filled the tank, my next FMM occurred 363 days later. Our friend Ari also chooses to run out before adding the minimum amount that will end the FMM (~1.5 gallons), and his FMMs usually occur ~313 days later (because the gas remaining in the lines after the tank is empty is enough to affect the overall "average age" of the ~1.5+ gallons now in the tank, lowering the next FMM date below the one year mark).

I’ve owned my 2012 Volt since April 2012, and drive 99% ev around home. I also tend to make a long vacation drive once a year or so (twice drove from Oregon to Michigan and back), so I try to time my last vacation fill-up to happen at least 100 miles from home. I reach home with plenty in the tank for any unexpected range extender needs, and I know it’s very possible I may make my next long trip before the next FMM window closes. After one of those fill-ups happened in late November, I discovered that if the most recent trip to the gas station was in mid to late winter one year, the desire to run the ICE and use up some of that getting-older gas for cabin heat the following cold season becomes very strong...

Toolworker said:

Next time it gets to FMM, will it give me the opportunity to decline and run for a gas station? Or do I have to anticipate it?

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Once the FMM message appears, you can postpone it until the next day, but each time you stop and restart the Volt the current day, the message will reappear, giving you the option again of postponing until the following day.

Once you say yes (or the next day), FMM will begin. The Gen 2 engine will not start until after a short delay once shifted into D (Drive), and will automatically continue at each vehicle start until fresh fuel is added. This differs from the Gen 1, which immediately starts the engine when you respond Yes. This applies to both EMM and FMM.

Note that you can’t Stop an FMM until you Start it, so don’t just postpone it, then drive to the gas station and add a couple of gallons, thinking to avoid it altogether. I suppose you could keep your "miles without gas" streak going by having a 1.5-gallon can of gas on hand or being next to the gas pump when you say Yes and shift into D long enough to get the engine to start, and then turning the car off and refueling, so you're not actually moving at any time during the FMM.

A posting some time ago indicated that one Volt owner postponed the FMM, then added 4 gallons to an existing 4 gallons. The following day the FMM message reappeared, and now he had 8 gallons of gas at the start of the FMM. Perhaps the computer sets a flag when it’s time for an FMM and doesn’t rerun an "average age of fuel" calculation until the next time gas is added after FMM has started. Perhaps if this owner had been able to add the ~1.5 gallon minimum amount to the tank after the FMM had started, the "average age of fuel" calculation would have been rerun to include the 4 gallons put in the previous day, and the next FMM would have been set for 6+ months down the road.

TheBlueFlash said:

Triggering FMM might be a sign a BEV is more appropriate for your driving habits. Why lug around 300 lbs. of dead engine weight and pay for synthetic oil changes every 2 years?

I'm not trying to troll, just genuinely curious, if you can go a full year without gas, why not just get a BEV and rent an ICE for those rare occasions you need it?

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I’ve experienced two FMMs in the 5+ years I’ve driven my 2012 Volt. If my 40+ miles/charge meets my around-town needs 99% of the time, the 238+ mile range of the Bolt is overkill.

If the choice is between carrying around 200 rarely-used ev miles in a battery, or a gas engine that can get me 300 miles at the cost of an oil change every two years, the range extender is the more prudent choice for me. Others may have different preferences arising from different driving habits.

When I do head out, it’s for hours of driving. I submit that when driving for hours on the interstate, most of the passengers don’t really care if it’s an electric motor or gas engine that’s moving the car down the road. Many want to drive straight through to grandma’s house without making a half hour refueling stop somewhere before getting there and then again on the way home.

With my Volt, I can drive an electric car from home to the interstate, and from the interstate to the destination. Furthermore, with my Gen 1 Volt, even if I arrive at my destination with a fully depleted battery, I’m still driving an electric car through those stop-and-go urban streets, and the 25-35 mph residential streets and 20 mph school zones, in a single-motor EV fueled by gas-generated electricity. GM refers to the Extended Range driving in the Gen 1 Volt as an "electric-like" experience. It’s hard to see, but for the use of gas to create the electricity, where driving a Gen 1 Volt in single-motor Extended Range mode differs from driving a BEV.