Possible to drive with no gas?

[Viking79]

Gas tanks always have a vapor head space (air space in the tank not designed to be filled). Some companies advertise the physical tank size, others the usable space. Depending on angle of slope you park on you might be able to partially fill the vapor space.

I suppose the trade off is if you want people complaining about the pump when their vehicle took more to fill than it supposedly holds vs having accurate estimate of range on gas. They really should advertise both.

 

[Techdup]

Yup, just did it this weekend. Was on a 250 mile trip. Was in HV mode most of the way. Was getting low on gas and I let it go to 0 when I was about 10-20 miles from my destination. Had plenty of charge to make it all the way. It was totally seamless. Didn't notice any difference when the gas range went to 0. When I filled up it was 6.9 gallons. Not quite 7, but that's because there is probably always a little left. Why do you say that the capacity is less than the advertised capacity?

I'm assuming your car switched over to EV automatically when you ran out of gas? Did you have any problem restarting the gas engine after fill up as stated by others?

 

[Viking79]

The car switches to EV and displays a warning, and sticks until you fill up (telling you to stop and fill with gas). My wife didn't test if the car will restart in this state (if you don't get gas).

 

[peterkronenberg]

I'm assuming your car switched over to EV automatically when you ran out of gas? Did you have any problem restarting the gas engine after fill up as stated by others?

As I said, it was totally seamless. No problems after filling with gas. And I never saw the message posted by Viking79

That was back in May that I did it, which was the first long trip after I bought the car. I think I might have let it go to empty one other time, but I don't usually make a habit of it. Right now, I'm due for fill-up. 1500 miles since the last fill-up and I have about 20 miles of HV range left.

 

[LegoZ]

When running in hv mode the gas engine will die if running and fail to restart in subsequent restart attempts. 0 indicated range is there just to scare you into getting fuel right now. When you filled at 6.9 you likely had another .2 gallons left before you were actually out of fuel. You likely had another 8 or so miles left before it was clear out. We are definitely in now you know mode. If you are in hv mode and are running single digits it will keep going after it runs out but it gets VERY angry. If you have EV range left you might want to go from HV mode back to Econ when indicated hv range hits zero as you gingerly get directly to a gas station.

 

[Viking79]

I wonder if the message came with a software update (like for HV range)? Or as you say maybe not totally empty. My wife's took 7.17 gallons to fill.

After filling with gas the engine started normally the next time it ran.

 

[LegoZ]

On a side note I had my first fill up since 7/1 on Friday night I had 2980 miles “on the tank”.
Comes out to 819 mpg (3.638 gallons to fill back up)

 

[Viking79]

Impressive! Lots of EV miles in 3 months too.

 

[peterkronenberg]

When running in hv mode the gas engine will die if running and fail to restart in subsequent restart attempts. 0 indicated range is there just to scare you into getting fuel right now. When you filled at 6.9 you likely had another .2 gallons left before you were actually out of fuel. You likely had another 8 or so miles left before it was clear out. We are definitely in now you know mode. If you are in hv mode and are running single digits it will keep going after it runs out but it gets VERY angry. If you have EV range left you might want to go from HV mode back to Econ when indicated hv range hits zero as you gingerly get directly to a gas station.

I still had plenty of charge left, so I just ran on EV until I got gas. And it switched seamlessly from HV to EV without me having to press any buttons. Not sure why it would be a problem if I'm running on EV. Obviously, if you run out of gas and charge, that would be the same as a traditional vehicle and the car would stop running. But again, it's not something I plan to make a habit of.

 

[GV Ottawa]

Two weeks ago I had the range fix bulletin applied. This weekend I had a long highway trip (used HV mode on the highway). On my way back, it was clear that my gas range was not going to get me home, but I had sufficient EV range left thus I kept going and didn't worry about my gas range hitting zero. I was on the highway when the gas range did get to zero. There was a completely seamless and automatic transition from HV to EV mode and I kept driving normally with no unexpected issues. When I got close to my house, I stopped at a gas station and filled the tank (25.00 litres added). No issues starting afterwards and I continued to my house in EV mode.

So, in summary, things worked exactly as I would have expected them to.... great car!

 

[GV Ottawa]

I forgot to note that I never received the warning image that Viking posted above on my display. I got a low fuel warning but certainly never saw a Vehicle Stop warning as depicted in that image.

 

[LegoZ]

I wonder if they have changed something to prevent you from actually running it dry now?

 

[GV Ottawa]

I wonder if they have changed something to prevent you from actually running it dry now?

Not sure I understand your question .... To my knowledge I did run the gas tank dry in my experience this weekend as there was zero gas range left and the car switched itself from HV to EV mode. I then was able to add 25.0 litres which is I believe is the stated tank capacity. The most I've ever been able to add previously has been 23.03 litres.

 

[KentuckyKen]

Not sure I understand your question .... To my knowledge I did run the gas tank dry in my experience this weekend as there was zero gas range left and the car switched itself from HV to EV mode. I then was able to add 25.0 litres which is I believe is the stated tank capacity. The most I've ever been able to add previously has been 23.03 litres.

I think what is being asked is how the car would handle, could it be damaged by, or would it even allow the fuel system to get to the point that the fuel pump all the way to the injector is aspirating air.
What you described is not that. You let the car sense when to stop the ICE and seemlessly switch over to EV at 0 usable gas left. It almost certainly won’t allow itself to get all the way to pumping air.

I don’t know if anyone has been brave or foolhardy enough to try this. I guess you might be able to by selecting HV Charge or by repeatedly selecting HV. It depends on the software protections Honda coded in.

The main thing is that you proved for us is that we can run our Claritys in HV all the way down to the point that it switches over to EV with no damage, problems, or worries.
Thanks for the observation and hats off to the Honda engineers.

 

[LegoZ]

Prior to the Software Updates the car in hv Mode ran down to the point the Engine stopped running, the ecm repeatedly tried to restart the gas engine prior to throwing up the warnings I described. It definitely differs from the experience GV Ottawa and Peter Krone Berg described. As I said ymmv but I’m not testing it again

 

[KentuckyKen]

Prior to the Software Updates the car in hv Mode ran down to the point the Engine stopped running, the ecm repeatedly tried to restart the gas engine prior to throwing up the warnings I described. It definitely differs from the experience GV Ottawa and Peter Krone Berg described. As I said ymmv but I’m not testing it again

No problem, @LegoZ. You only have to be brave once to be our hero!

 

[GV Ottawa]

I think what is being asked is how the car would handle, could it be damaged by, or would it even allow the fuel system to get to the point that the fuel pump all the way to the injector is aspirating air.
What you described is not that. You let the car sense when to stop the ICE and seemlessly switch over to EV at 0 usable gas left. It almost certainly won’t allow itself to get all the way to pumping air.

I don’t know if anyone has been brave or foolhardy enough to try this. I guess you might be able to by selecting HV Charge or by repeatedly selecting HV. It depends on the software protections Honda coded in.

The main thing is that you proved for us is that we can run our Claritys in HV all the way down to the point that it switches over to EV with no damage, problems, or worries.
Thanks for the observation and hats off to the Honda engineers.

Ah, I get it now!! No doubt you are correct Ken - thanks for the clarification.
Cheers,
Gary

 

[Pushmi-Pullyu]

Thanks for the observation and hats off to the Honda engineers.

Indeed! I have been impressed by reports of how well the Clarity PHEV performs as a "switch-hitter", switching between gasmobile power and EV power, and how well its dual drivetrain is engineered. Now I'm even more impressed!

 

[Umm Yeah]

When I bought my Clarity back in May, the dealer specifically warned me not to run out of gas because of the battery ran down and it tried to switch back to gas mode, it could damage the system. It sounds like they've addressed it with a software patch from the discussions above though.

Sent from my SM-G955U using Inside EVs mobile app

 

[Electra]

Hmm... I have never been able to put in more than 13 gallons in my CX5 even though the advertised capacity is 14+. Even accounting for the little bit left by the time I rolled into the gas station, I figured that cars don't take their advertised capacity. Same with the Buick that I traded the Clarity for, never took more than 20.5 even though it was a 22-gallon tank.

Did you add more gas when the pump clicks off? With my previous ICE cars, I could usually get 1 more gallon after the pump clicks off. With my current Prime, I can only get 0.3 gallons. I'm not sure about the Clarity, has anyone tried to see how much more gas they are able to add after the pump clicks off?

I searched about your CX5 and this is what another person said:
"I also have the same problem of filling up the tank. Each time I fill up the tank in the gas station, the trigger triggers very soon (11.7 gallons); then I continue filling little by little and I get 3.5 additional gallons; This takes away a lot of time and I do not like it. Check my CX 5 below and I could see that the inlet tube to the tank is connected by half the height instead of the top of the tank; this is a bad design. Mazda should fix it."