[Jd3]

Hello Gen2 Volt guru's ... I love this forum for the deep knowledge base about our cars. I have a subtle question for everyone: I have owned my 2016 now since new (about 3 years), and it's been a great drive so far with few issues (a couple of recalls early on ... and then nearly bulletproof since). I tend to average around 90% plus on full electric mode, so to maximize my range, I pump my tire pressures up to about 40psi all around and I only carry 1-2 gallons of gasoline for the occasional extended trip (why carry weight you don't need, and will cost you electric miles?)

Last night, I took a trip that had me run out of battery power about 3 miles from my house -- as usual, ZERO issues -- the ICE fired up seemlessly and took me home -- but this got me to thinking:

In the conventional ICE world, one of the worst things you can do (as far as wear and tear) is to take short trips ... where the ICE doesn't have a chance to fully warm up. So, if I'm using the Volt's ice for 5 minutes, it's definitely not coming up to temp.

Also: conventional wisdom on using ICE cars in the winter is leaving the gas tank full (to help prevent condensation). My car is garaged almost every night, but may spend the day out in freezing temps during the day at work.

So:
1) should I modify my driving habits,, and if I'm marginal on electric power to kick in the ICE early so that it WILL have a chance to fully warm up before parking for the night?
2) Should I be adding some sort of stabilizer/de-icer to the gas for long term waiting??

thanks in advance,
Jd

 

[turboguy327]

Yes, if it’s going to run, give it a fair chance to warm up.

Use E0 fuel. No ethanol laced fuel belongs in any fuel tank. Everything will be better off. The volts tank is sealed to make fuel storage as good as it can be but help it out.

 

[VoltAP1]

Meh, the ethanol thing is way overblown. It's not bad to have in the tank, and if anything it helps remove small amounts of moisture ("gas line dryer" is just an alcohol of some sort).

As for being nice to the ICE, yes, I really try to make sure it'll run and get the coolant up to temperature for at least ~5-10 mins to have a chance at getting some heat in the oil if it will ever run. If I'm going on the highway for a period and know I'll be over my EV range, I'll run it a bit before getting on the highway to warm it up, then the extended usage will get the oil up to temp.

Yes, this probably burns a few cups more gas than it would if I maximized the EV range over a season/year, but I guess I'm a bit old school in that I will go out of my way to treat my mechanical/electrical machines with as much respect and care as I can. Some people take to that be just maintaining them to a minimum standard, but I also think it's important to treat them as gently as possible while doing the job that you need done.

 

[Steverino]

See your owner's manual for do's and don'ts on fuel additives of any kind.

 

[jcanoe]

1) GM specifies 100% synthetic oil for use in the Volt. Even so, if possible when the ICE runs it is better for the coolant and engine oil to reach full operating temperature. If I am going to drive my Volt at the limit or just beyond battery range I will use Hold mode for part of the trip to ensure that the ICE runs for at least 10 minutes / 10 miles on the highway. The driver's information console can display engine coolant temperature, I run the engine until the coolant temperature has stabilized at between 190F - 205F. Usually arrive back home with 1 bar displaying on the battery state of charge display. I know I am using slightly more gas than I would otherwise use but I prefer to have fully warmed up the engine, driven any moisture from the oil and crankcase.

2) The Volt's fuel tank is sealed, pressurized so there is no way for condensation moisture to enter the fuel system. The Owner's Manual recommends keeping 3 gallons of fuel in the Volt's fuel tank (1/3rd full) unless you are planning a trip that will require that you use gas. See the Volt Owner's manual regarding adding any fuel additives to the fuel tank.

 

[Andy00778]

Here is something I do for an occasion where I can’t make it home on electric in the summer. I drive on hold mode the first leg of the journey and switch to electric when I estimate that I am within electric range. That way I return home with a substantially cooler engine, which, when I park the car in the attached garage, reduces the heat impact on the house ( and thus AC load). I look at the overall efficiency of the house and car, not just the car.

 

[barich]

If I am taking a long enough trip where I will need to use the ICE, I put it in hold mode and let it fully warm up and then switch out of it on my return trip when there are a few more miles on the guessometer than there are remaining to my house. This means I leave a tiny bit of electric range on the table, but I'll trade that off for keeping the engine in better shape. If the engine is never fully warmed up, gasoline and water never have the opportunity to evaporate out of the oil, and any carbon buildup never has a chance to burn off.

 

[obermd]

I suspect this issue is somewhat overblown. My wife's 2007 Solara has 45K miles on it. She's the only owner of the car. For about 30K of those miles it was one mile here, one mile there, etc., never giving the engine a chance to warm up. The engine is still in good shape. It also gets an oil change with full synthetic every fall even though the owner's manual says maximum of 6 months between oil changes.

 

[Don M]

If I am taking a long enough trip where I will need to use the ICE, I put it in hold mode and let it fully warm up and then switch out of it on my return trip when there are a few more miles on the guessometer than there are remaining to my house. This means I leave a tiny bit of electric range on the table, but I'll trade that off for keeping the engine in better shape.

I do the same. When think may need a few ICE miles to complete my trip, I try to use those on the freeway or at least on a portion of my trip where I'll be driving at relatively high speeds with no stop and go. 8 or 10 miles of that warms things up and I switch back to Normal mode. I *always* leave a few EV miles on the table, as I try to get home with 3 or 4 miles left over. So far, I've never had the car switch from EV to ICE on it's own and I'm fine with that - I much prefer doing it this way to having it switch a couple miles from home as the OP describes

Don

 

[JRRF]

2) The Volt's fuel tank is sealed, pressurized so there is no way for condensation moisture to enter the fuel system. The Owner's Manual recommends keeping 3 gallons of fuel in the Volt's fuel tank (1/3rd full) unless you are planning a trip that will require that you use gas. See the Volt Owner's manual regarding adding any fuel additives to the fuel tank.

The owner's manual only recommends this as it relates to efficiency:
"The weight of excess cargo in the
vehicle affects efficiency and range.
Avoid carrying more than is needed.
If fuel is not regularly used, consider
keeping the fuel tank only one-third
full. Excess fuel weight impacts
efficiency and range."

Gasoline weighs about 6 pounds/gallon. So the impact of a full 8 gallon tank is less than 50 lbs. Think about the difference in range with and without a small child in your car. It's really completely negligible.

 

[JRRF]

So:
1) should I modify my driving habits,, and if I'm marginal on electric power to kick in the ICE early so that it WILL have a chance to fully warm up before parking for the night?
2) Should I be adding some sort of stabilizer/de-icer to the gas for long term waiting??

The short answer to these questions is: no and no. GM is not the least bit concerned with either of these issues because they put a 5/60 warranty on the drivetrain. There are plenty of grannies who drive their Oldsmobiles 5 miles to the store and back each week, and they are still driving Oldsmobiles.

 

[obermd]

The owner's manual only recommends this as it relates to efficiency:
"The weight of excess cargo in the
vehicle affects efficiency and range.
Avoid carrying more than is needed.
If fuel is not regularly used, consider
keeping the fuel tank only one-third
full. Excess fuel weight impacts
efficiency and range."

Gasoline weighs about 6 pounds/gallon. So the impact of a full 8 gallon tank is less than 50 lbs. Think about the difference in range with and without a small child in your car. It's really completely negligible.

Agreed. The reason GM puts this statement in is because the EPA City MPG rating is very heavily dependent on the GVWR. My experience is that within reason the weight of the vehicle simply doesn't make a difference in real world driving.

 

[Jd3]

Some great answers everyone ... i think at the limit, it is probably a decent idea to heat the car up to operating temp on the highway ... for 10 miles, it's what: a quart of gas? Negligible, and I think good to heat everything up. And I also agree that the difference between 1 gal and 3 gallons is probably negligible ...

Appreciate everyone's comments. Thx!

 

[JRRF]

Some great answers everyone ... i think at the limit, it is probably a decent idea to heat the car up to operating temp on the highway ... for 10 miles, it's what: a quart of gas? Negligible, and I think good to heat everything up. And I also agree that the difference between 1 gal and 3 gallons is probably negligible ...

Appreciate everyone's comments. Thx!

Also, if the car feels that it needs to run the engine for a while, it will do so in maintenance mode, and you won't be able to stop it.

 

[DocWheezer]

Some great answers everyone ... i think at the limit, it is probably a decent idea to heat the car up to operating temp on the highway ... for 10 miles, it's what: a quart of gas? Negligible, and I think good to heat everything up. And I also agree that the difference between 1 gal and 3 gallons is probably negligible ...

Appreciate everyone's comments. Thx!

Don't forget:
Remember that the Fuel pump is sitting at the bottom of the fuel tank and is cooled with what fuel is in the tank.
The added weight of even a half tank of gas is negligible.
https://www.bellperformance.com/blog...ur-Fuel-System
Wearing Out The Fuel Pump
The fuel pump has the function of pumping fuel. I know, revolutionary, right? It's a precise piece of machinery that gets its lubrication from the gasoline fuel. When there's not enough gas in the tank, the fuel pump doesn't get the same level of protection as it would otherwise. If you run the car low on fuel consistently, you can wear out the fuel pump prematurely, over-stressing it and making it hotter. The caveat here is that it's more likely to happen if you do this over a longer period of time.
Plus
Auto Maintenance: Why You Can't Ignore the Fuel Pump.
Taking care of your fuel pump
If properly cared for, several highly rated auto mechanics say fuel pumps should last the entire life of a car.

To extend the life of your fuel pump, never let you car’s fuel level fall below a quarter of a tank, says David Schneider, co-owner of highly rated Dare Automotive in Dayton, Ohio.

“The fuel pump should last as long as you own the car, but people tend to run the fuel tank too low, which causes them to wear out,” Schneider says. “The fuel in the tank cools the pump. But when the gas runs down to empty, the pump will overheat.” If the tank is empty and new gasoline is pumped in, it can cause thermal shock to the pump, Schneider says.

 

[Jd3]

Good post Doc ... I'll be adding gas for sure!

 

[FI Spyder]

Keeping your gas tank full is a waste. A heavier car uses more electricity than a lighter one. True the difference isn't much when comparing it to a 2 ton car but over the life of the car, why not keep it as light as you can? As far as keeping gas in it to cool the in tank fuel pump, the pump is at the bottom of the tank and will be covered with fuel down to where you'll get the low fuel warning, remember it's a small tank. Cars used to have gas recirculation to cool the pump (some where external) but modern cars don't have/need that. The argument for keeping a tank full of gas to cool the pump is arguing how many angels can dance on the head of a pin. That's why GM recommends keeping just a couple gallons in it. The pressurized fuel tank is not to prevent condensation as much as to prevent the lighter components in gasoline evaporating and making it go stale. As for marginal EV range, if you are going to need ICE, use HOLD (at the beginning if it's cold and you can use the engine heat for initial heating) long enough to warm the engine to dispel any moisture from oil and make the engine maintenance mode not necessary.

 

[DocWheezer]

Who mentioned a Full Tank of Gas?

 

[Stromfahrer]

I had the same question when I first bought my 2013:

https://gm-volt.com/forum/showthread.php?55937-Short-ICE-sessions-bad

 

[FI Spyder]

Who mentioned a Full Tank of Gas?

I did. Driving around with a full tank of gas is a waste. Engineers go to all lengths to lighten and shed every pound. Unless you are trying to minimize condensation in an older car where gas tanks are no longer available.