GM Volt Forum banner
1 - 7 of 7 Posts

·
Registered
Joined
·
4,855 Posts
Discussion Starter · #1 · (Edited)
So yesterday my 2017 Volt determined that the fuel (approx. 4 gallons) in my Volt was too old and needed to be used up. To be certain, the last time I added fresh fuel was 6 months ago when I added ~3 gallons to the 3 gallons that were remaining at that time. Between yesterday (before entering FMM) and today (after starting FMM) I have used ~2.5 gallons with 1.5 gallons of old fuel remaining. For those that have experience with FMM, how low did you allow the fuel tank to get before you added fresh fuel?

While I have my Volt in FMM I will attempt to answer the question of what happens if you initiate preconditioning. (Will the ICE start?) [Answer: No, it did not.] I will also initiate preconditioning while plugged in although I am fairly confident that the ICE will not start since it is not that cold (~40F) and I have Engine Assist Heat Plugged In set to No.

[Edits: So I completed my first FMM having driven ~180 miles on gas to use up the remaining old fuel.

The Low Fuel warning indicator came on with approx. 1 gallon of fuel remaining.

Once the fuel level was approx 1/2 gallon the estimated range switched from X number of miles to just reading Low.

Gas engine propulsion halted due to lack of fuel within 3 miles of what I had earlier that day estimated for my remaining gas range.

I only had to drive with Reduced Propulsion for less than 1 mile to limp to a gas station but that was enough to understand that I would not want to try and accelerate onto a highway with reduced propulsion activated. It felt like my Volt was running on no more than 25% of normal power.

I purchased $13 of 87 octane regular Sunoco brand fuel @ 2.65/gal; 4.25 gallons went into the Volt's fuel tank, the remaining fuel went into a fuel container for use in my snow blower.

When I started the Volt after refueling the fuel tank the gas engine range for just a few seconds, then shut off. Propulsion on battery returned to normal power levels.]
 

·
Registered
Joined
·
1,999 Posts
While I have my Volt in FMM I will attempt to answer the question of what happens if you initiate preconditioning. (Will the ICE start?) I will also initiate preconditioning while plugged in although I am fairly confident that the ICE will not start since it is not that cold (~40F) and I have Engine Assist Heat Plugged In set to No.
I doubt the engine will run during precondition if you have it set to NO, for legal reasons.
 

·
Registered
Joined
·
952 Posts
For those that have experience with FMM, how low did you allow the fuel tank to get before you added fresh fuel?
Personally, I let mine run all the way out (HVB was full) so I would have the best bet of starting again with a clean slate rather than the system calculating x% of the tank was still original.
 

·
Registered
Joined
·
1,982 Posts
...For those that have experience with FMM, how low did you allow the fuel tank to get before you added fresh fuel?
It’s December. Your unexpected FMM brings you an unanticipated benefit. You now have the opportunity to keep your cabin toasty warm during your commute by running your engine to burn up the old gas.

I’ve had 3 FMMs in the 6+ years I’ve been driving my 2012 Volt. I drive 99+% ev around town, but about once a year I take a long vacation drive that involves filling the gas tank a few times, including a final one before arriving home again, leaving me with enough gas to avoid range anxiety for a year. Sometimes the next vacation trip doesn’t happen within the 12 month interval limit, and the FMM arrives.

I prefer to continue the FMM until I run out of gas, so the new gas I put in will postpone the next FMM for the maximum amount.

To end the FMM, I fill my empty tank, and, thanks to a minimum amount of gas remaining in the lines after the engine stops because the tank is emptied, the next FMM is 363 days later, not 365. If you end your FMM by running out of gas, adding less than a full tank of fresh gas will shorten the time until the next FMM. Our forum friend Ari C also empties his 2012 Volt’s tank during an FMM before refilling with a minimum amount of gas (~1.5 gallons). Because the residual "old gas" remaining in Ari’s Volt’s system is a larger percentage of the total volume, his FMMs seem to occur just 318 days later.
 

·
Registered
Joined
·
4,855 Posts
Discussion Starter · #6 ·

·
Registered
Joined
·
3,439 Posts
That sounds very similar to what happens when a Gen 1 runs out of gas. The differences are that the miles to empty stops displaying with about 1 gallon remaining, and the reduced propulsion mode leaves you with about 2/3 of the original power, which I thought was adequate to get by for normal driving.
 
1 - 7 of 7 Posts
Top