[jljeeper]

For the past two days my engine has been running in (in gas mode) my entire commute even though I have a full battery. It also happened to be cold the last couple of days (20s F in the morning but high 48 F in the afternoon) and it also happens to be that the gas is nearly a year old. The part that concerns me is I don't get any message telling me why it is running (like I did on my Gen 1) Engine Maintenance, ERDTT or Fuel Maintenance.

I assumed since it was 48 degrees on my way home and the engine was still running that this must be due to old fuel but shouldn't I see a message? Do we have to guess now? My Gen 1 told me why the engine was running for all scenarios

Thank you for any info, before I have to take it in to the dealer

Jon

 

[lagagnon]

The ERDTT and fuel maintenance messages pop up on screen for only about 5 seconds and then go away - is it possible you just missed them while watching the road??

 

[Barry]

My guess is fuel maintenance mode and maybe the message appeared briefly and you missed it. I am not familiar with how that message is displayed. Maybe another member knows.

 

[supercub]

Well, I'm anxious to see other responses since I have basically the same symptoms in my gen 2 2017. Being in Canada we're metric and around -3 celsius (roughly around 26F) with a full battery my engine comes on but not full generator mode, it seems both engine and battery are equally motoring the car. It does it for sometimes 30 - 40 km and then I'm on battery for a while, sometimes short sometimes 8-10 or 15 km.... BTW to my knowledge no warning light comes on.....

 

[lagagnon]

...again, there is no "warning light"! It is a brief 5 second message on the DIC. See page 143 of your manual to "defer" the ERDTT. This subject has been done to death on this forum and there are already numerous threads to search for more info....

 

[Barry]

Well, I'm anxious to see other responses since I have basically the same symptoms in my gen 2 2017. Being in Canada we're metric and around -3 celsius (roughly around 26F) with a full battery my engine comes on but not full generator mode, it seems both engine and battery are equally motoring the car. It does it for sometimes 30 - 40 km and then I'm on battery for a while, sometimes short sometimes 8-10 or 15 km.... BTW to my knowledge no warning light comes on.....

To add to lagagnon's reply, this is referred to as "engine assisted heating" in the manual. You can change the settings for that, although you can't turn it off completely (without some modification).

 

[jljeeper]

Yes I am aware it is a short message. I owned a Gen 1 for 5 years and this is my first full year with a Gen 2. I have seen the engine maintenance come on in my Gen 2. Last year I remember seeing the ERDTT a couple of times (not seeing it this time). I am just not familiar with Fuel Maintenance since I have never been here. Could it be that I am in Fuel Maintenance and no need to have ERDTT since its burning off the old gas? I assumed this is what is happening but I have been looking for the message to pop up and am not seeing it.

 

[Barry]

Yes, exactly. I think you should assume it is fuel maintenance mode. If it still runs after adding gas, then you have more to figure out.

 

[wordptom]

A reasonable explanation for an engine running whenever the Volt is turned on and shifted into drive, especially when the gas is known to be "about a year old," is that the car is experiencing a Fuel Maintenance Mode (FMM) episode.

With my Gen 1 Volt, a message indicating this is happening should appear briefly each time you start the car, until something is done to adjust the "average age" of the gas in the tank. I have no reason to think this doesn’t also happen with a Gen 2 Volt - briefly appearing each time the car is started. The OP could just try turning the car off and then back on again to see if such a message appears.

Alternatively, such a message might still be available as you drive. The Gen 1 Volt’s Driver Information Center’s control knob is on the dashboard, to the left of the steering wheel. Rotating it to the Message display and pushing Select should bring up any available messages. The DIC control for the Gen 2 Volt, I think, is on the right side of the steering wheel.

If this is an incident of FMM, then the original FMM message would have appeared briefly when the car was started that day (and each time during the first day the car is restarted), saying it’s time for an FMM, it can be postponed to the next day, start now yes or no. If yes is not chosen, then on the following day, the message appears again with no option to postpone. Once the car is put into Drive, the FMM begins. The ability to drive on battery power is no longer available, even with a fully charged battery, until the FMM is ended. Some do it by adding fresh gas to existing gas. Some burn up most or all of it first, and then add fresh gas.

A possible FMM does bring up this question. If an FMM is in progress, can you precondition the car without running the engine?

 

[jcanoe]

A reasonable explanation for an engine running whenever the Volt is turned on and shifted into drive, especially when the gas is known to be "about a year old," is that the car is experiencing a Fuel Maintenance Mode (FMM) episode.

With my Gen 1 Volt, a message indicating this is happening should appear briefly each time you start the car, until something is done to adjust the "average age" of the gas in the tank. I have no reason to think this doesn’t also happen with a Gen 2 Volt - briefly appearing each time the car is started. The OP could just try turning the car off and then back on again to see if such a message appears.

Alternatively, such a message might still be available as you drive. The Gen 1 Volt’s Driver Information Center’s control knob is on the dashboard, to the left of the steering wheel. Rotating it to the Message display and pushing Select should bring up any available messages. The DIC control for the Gen 2 Volt, I think, is on the right side of the steering wheel.

If this is an incident of FMM, then the original FMM message would have appeared briefly when the car was started that day (and each time during the first day the car is restarted), saying it’s time for an FMM, it can be postponed to the next day, start now yes or no. If yes is not chosen, then on the following day, the message appears again with no option to postpone. Once the car is put into Drive, the FMM begins. The ability to drive on battery power is no longer available, even with a fully charged battery, until the FMM is ended. Some do it by adding fresh gas to existing gas. Some burn up most or all of it first, and then add fresh gas.

A possible FMM does bring up this question. If an FMM is in progress, can you precondition the car without running the engine?

If the Volt is plugged in while preconditioning and you have set Engine Assist Heat Plugged In to be No then the ICE should not start while preconditioning. The same risk that exists when running the ICE to precondition the cabin would apply to FMM, not wanting carbon monoxide to build up inside a closed garage space.

 

[wordptom]

If the Volt is plugged in while preconditioning and you have set Engine Assist Heat Plugged In to be No then the ICE should not start while preconditioning. The same risk that exists when running the ICE to precondition the cabin would apply to FMM, not wanting carbon monoxide to build up inside a closed garage space.

That’s the behavior I would expect, but FMMs are rare, and if the battery is fully charged, would preconditioning allow battery power to be drawn for cabin climate conditioning (whether or not you are plugged into the wall), or would an FMM be among those conditions "under which a remote start may not work?"

 

[jcanoe]

That’s the behavior I would expect, but FMMs are rare, and if the battery is fully charged, would preconditioning allow battery power to be drawn for cabin climate conditioning (whether or not you are plugged into the wall), or would an FMM be among those conditions "under which a remote start may not work?"

The Volt will precondition the cabin using only the electric heat (without the gas engine running) when the Volt is not plugged in unless the ambient air temperature is below 35F or below 15F (if Engine Assist Heat is set to deferred). In the 2019 Volt the Deferred setting will prevent the ICE from running to generate heat for the cabin until the ambient air temperature falls to -14F.

 

[timoshev]

Top off tank. Report back.

 

[srmarti]

...again, there is no "warning light"! It is a brief 5 second message on the DIC. See page 143 of your manual to "defer" the ERDTT. This subject has been done to death on this forum and there are already numerous threads to search for more info....

There's really nothing to "warn" about. There's just an informational message. It sounds like normal operation.

 

[jljeeper]

wordptom

Thank you for that explanation, I solved my confusion. I will post separately below

Your question...."If an FMM is in progress, can you precondition the car without running the engine?"

I will answer your question with my direct experience:. Mine has been in FMM for 3 days and I am plugged in to L2 in my closed garage. I precon every morning for 3 days. No the engine does not come on. I read today that during FMM and EMM the engine will not start until briefly after the car is put into Drive. I read this on the E-manual on the center stack.

 

[jljeeper]

Solved Engine running No message

Well everyone was right, It was FMM,
There was a message, A tiny one. I may have missed the first few messages but I now know that the subsequent message is very small, about 1/2 inch high at the bottom of the stack screen and it disappears quickly. Very easy to miss. Not at all like a Gen 1 where it is in your face large and I think you have to acknowledge it (Right?). If you see this tiny tiney message you can tap the (More) to get some info. Thank you to all for helping me open my eyes. I have no idea why there is a dismiss button, by the time you even focus it disappears anyway. I also found out that it will keep burning gas until it is all gone or you fill the tank enough to satisfy the dilution of the old fuel. Looks like I'm getting some gas tomorrow. Its also my birthday so I guess that's when I get gas now once a year.

 

[jljeeper]

Alternatively, such a message might still be available as you drive. The Gen 1 Volt’s Driver Information Center’s control knob is on the dashboard, to the left of the steering wheel. Rotating it to the Message display and pushing Select should bring up any available messages. The DIC control for the Gen 2 Volt, I think, is on the right side of the steering wheel.

I remember the Vehicle Message area in my Gen 1 but could not find it on my Gen 2. I thought about that too. I looked several times. They must have did away with that too.

I liked that the Gen 1 would track gallons used on the two trip meters, that is now gone on Gen 2.

 

[wordptom]

Here’s something just brought to my attention as I reviewed the Owner’s Manual info on the maintenance modes EMM and FMM. As jljeeper’s pictures show, those messages appear on the center stack (or infotainment) display, not behind the wheel on the DIC. The initial notifications offer an option, start now or postpone until the following day, so they need to appear on a touch screen. Also, they are described in the manual as the EMM request screen and the FMM request screen, rather than "messages."

 

[Cord]

After a BIG BURN and adding gas you may still be gas and not electric for a short time.

 

[jljeeper]

After a BIG BURN and adding gas you may still be gas and not electric for a short time.

You are exactly right. I was planning to post this as a follow up. Mine continued for 10 miles on gas then went to battery. I assume that is to use up what is in the fuel line that has not been mixed with fresh fuel