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Discussion Starter #1
I haven't had it happen yet, but what do you do when EMM pops up? Is it best to switch to hold mode and just drive normally? Basically, what would be the most efficient thing to do when it pops up?
 

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The car is smarter than any of us. Let it do it's thing. That is unless you are making a really short trip and expect to do a longer one later, in which case I've selected to delay EMM. Once I used hold and there was no benefit. I think EMM uses specific RPMs and times to achieve a specific objective and there's no point in trying to out think it.
 

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The car is smarter than any of us. Let it do it's thing. That is unless you are making a really short trip and expect to do a longer one later, in which case I've selected to delay EMM. Once I used hold and there was no benefit. I think EMM uses specific RPMs and times to achieve a specific objective and there's no point in trying to out think it.
Agreed. Just had this happen yesterday. Started car, EMM message pops up. I knew the first leg of my drive would be less than 10 minutes, so I hit the "delay" button. Finished first errand, got back in and restarted, then let the car do its thing during the 20 minute drive to the next destination.

Didn't seem to add anything to the battery (though I had the A/C blasting and was going 70 mph most of the way, so couldn't really tell), and my gas miles remained unchanged (which would NOT be the case in Hold mode).
 

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EMM (Engine Maintenance Mode) happens every 6 weeks that ICE is not used. There is no need to run the car in Hold mode. EMM will automatically run through a pre-set program. It runs for a few minutes and consumes about 0.03 gallons of gasoline. User has the ability to postpone EMM for up to 24 hours. If you use ICE regularly, you will not encounter EMM.

Be warned that, if EMM is pending and you perform a remote start (pre-condition), ICE WILL come on even if the car is plugged in.
 

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Discussion Starter #6
I thought I would ask the original question well before EMM popped up, as I only had my car for 2 weeks. Ironically, only 10 minutes after I asked it, it popped up in my car. I skipped it, hoping to read the responses here first. I then let it run on the trip home. It took about 15 minutes, and I never even knew the engine was running, if the display never told me.
I was wondering why EMM came up when I had my car only 2 weeks. Then I realized my car was manufactured exactly 6 weeks ago.
 

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Agreed. Just had this happen yesterday. Started car, EMM message pops up. I knew the first leg of my drive would be less than 10 minutes, so I hit the "delay" button. Finished first errand, got back in and restarted, then let the car do its thing during the 20 minute drive to the next destination.

Didn't seem to add anything to the battery (though I had the A/C blasting and was going 70 mph most of the way, so couldn't really tell), and my gas miles remained unchanged (which would NOT be the case in Hold mode).
EMM usually uses less than a cup of gasoline, and I'm not sure that the gas-o-meter even pays attention to less than a tenth of a gallon.
 

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Whenever I have a pending EMM, remote start fails.
Do you have low gas or an active MIL? Remote start will not go in either condition.
If not, they may have fixed this fatal flaw in gen2.

Gen1 will start the engine when remote starting (even if plugged in with engine disable option) and EMM is due.
 

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I believe it has to get the engine to optimal temperature (same temp it climbs to for winter ERDTT) based on watching the engine temp for each. I seem to recall hearing this elsewhere to, but will leave ya to do the Googling to confirm or deny:)
 

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I believe it has to get the engine to optimal temperature (same temp it climbs to for winter ERDTT) based on watching the engine temp for each. I seem to recall hearing this elsewhere to, but will leave ya to do the Googling to confirm or deny:)
It's higher than ERDTT and has to hold it there for longer. ERDTT peaks and drops instantly as heat is being sucked out of the system.
I've posted temps/times/etc for EMM on these forums (and many data sets over the past two years). From the sounds of it, gen2 is not much different, but takes longer to complete.
 

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When the EMM message pops up, it usually is the first thing in the morning when the battery is fully charged. I always say "no," and drive several miles to get the battery SOC down a bit. I found if the battery is already full EMM cannot run the engine very hard, so it does not warm up fast, extending the time required for EMM a great deal. Since I am just driving on slow streets the car doesn't use much power, but if the battery is not full the Volt will charge it up to load the engine properly.

On the next start-up of the day I will say "yes" to EMM, but only if I plan to drive further than about 5 miles. That way EMM will be completed before I reach my destination. Otherwise EMM will resume on the next engine start.

I drive a 2014, gen 1 Volt.

GSP
 

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I haven't had it happen yet, but what do you do when EMM pops up? Is it best to switch to hold mode and just drive normally? Basically, what would be the most efficient thing to do when it pops up?
Whack it like a mole!
 

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EMM popped up last week for me, as I was leaving work. Since I usually have to pull a banzai run to get onto the highway, I let it do it's thing. It was over in just a few minutes and used 0.02 gallons.
 

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Embrace the SUCK. I take advantage of it by CRANKING the AC or HEAT or drive it like a vette.
 

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We never had an issue with EMM on our 2014 Volt and now our 2016 Volt. At least once or twice a month we take a ride to Portland Oregon or Longview Washington which gives the gas engine plenty of exercise after the 50-60 miles on electric. MPG just on gas is mid 40's, last trip was 48 mpg's, so even on gas we still get as good or even better mpg's on gas than perhaps a Civic or Corolla with our 2016 Volt.
 

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When the EMM message pops up, it usually is the first thing in the morning when the battery is fully charged. I always say "no," and drive several miles to get the battery SOC down a bit. I found if the battery is already full EMM cannot run the engine very hard, so it does not warm up fast, extending the time required for EMM a great deal. Since I am just driving on slow streets the car doesn't use much power, but if the battery is not full the Volt will charge it up to load the engine properly.

On the next start-up of the day I will say "yes" to EMM, but only if I plan to drive further than about 5 miles. That way EMM will be completed before I reach my destination. Otherwise EMM will resume on the next engine start.

I drive a 2014, gen 1 Volt.

GSP
The net result of a gen1 EMM is electricity used.
It does not generate electricity for the duration of the test. It will end up using more than it generates, which only happens for the first minute or so @ ~6kW (not even enough to fill the over-regen buffer).

No need to go out of your way to use up some battery first.
If it doesn't complete before you arrive at your destination, put it in park and press the pedal down. It will rev higher and finish faster.
 

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The net result of a gen1 EMM is electricity used.
It does not generate electricity for the duration of the test. It will end up using more than it generates, which only happens for the first minute or so @ ~6kW (not even enough to fill the over-regen buffer).
(And when you ask yourself why not generate? Because unloaded engines use a hell of a lot less fuel, and EMM's goal is just to get some number of revolutions done as efficiently as possible and make sure oil and coolant go where they're supposed to go when they need to go there.)
 

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I haven't had it happen yet, but what do you do when EMM pops up? Is it best to switch to hold mode and just drive normally? Basically, what would be the most efficient thing to do when it pops up?
I guess it depends on what your goal is. If your trying to get the most EV miles. Delay it. Then when parked somewhere. Let it run while the car is parked, and you wont get an miles under gas. If your just wondering on energy saving, hopefully within that 24 hr window, you have some highway driving. Delay it then when you get on the highway, go into hold mode.

Otherwise just let it go.
 
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