[WARNING] Running out of gas (Gen III)

efusco, I tried.
When others, (and I do this too) respond to hyperbole and NOT to the answers/ideas about the topic at hand, it just all spins out of control.
So I will repeat myself here, as I am interested what you think about these as possible reasons for the change.

 

You know your aircraft fuel load to a fraction of an hour. Without user calibration, my various cars have displayed a two hour disagreement.

You love the precision of flying, but deride attempts to bring similar precision to driving.

Bob has tried to bring some fuel precision to a particular car model. If you applied your own rule to one of my past cars on my routes, you would have found yourself stranded numerous times -- by the time it started giving warning, it would already be too late to get to an open station. To plan ahead with any precision, before the car gives warning, I want to know the fuel starvation point better than a wishy-washy, 2-hour-uncertain, "refill at X gauge level" rule.

 

If someone is prone to running out of gas, why not have a second 1-gallon gas tank installed? At the flip of a switch, you could instantly while still coasting drop another gallon in the tank and off you go.

Why travel one mile under electric power when you can drive 50 on a gallon of gas?

 

I have been left stranded in the middle of the interstate before. There were eight lanes of traffic, no possible way for me to exit the vehicle safely, and no way to reach either shoulder. Was it a Prius I or II? No. Was it because I ran out of fuel? No. My fuel system simply decided it was a good time to kick the bucket.

If I was in a Prius I or II, I could have made it to the side and the rest of this would never have taken place.

Over the next half hour (the time it took before an officer could halt traffic long enough for me to push the vehicle off the road), I witnessed four accidents. Two were luckily low speed accidents. Two were at moderate speed (25-35mph). While I was lucky enough not to be involved in the accidents themselves, my stalled vehicle was clearly the catalyst. I watched one of the drivers of the two moderate speed accidents as the accident took place. He was looking right at me when his pickup truck climbed right onto the cars in front of him. I never found out if everyone made it out ok. The two low speed accidents took place after the drivers were rubber necking, saw that they were closing too quickly on the rubber necker in front of them, and weren’t able to stop their vehicle in time to avoid a fender bender.

This was one of two times in my life where I was stuck in my car, terrified, and helpless to do anything about it. I was 19 or 20 at the time of the above. I am now 34 and have a family to think about.

Now, we (posters to PC) have apparently become polarized on this issue. One side apparently railing against Bob or anyone they consider stupid. And another side looking for support to get a feature returned to an otherwise very cool vehicle.

I'm not on PC to debate what is stupid or what defines a safe vehicle. I am looking for helpful information to help educate me and make me a better customer.

So, what can we do? Do we have any recourse with Toyota's engineering team? Does anyone have contacts within Toyota? Maybe we can get to the bottom of this and discover the real reason they put in the lockout.

It could simply be an oversight and only require a software update. Lord knows I run across software bugs all the time. If its not a bug, they might listen to enough of us and be willing to allow us the ability to override the EV lockout. Thus allowing us the ability to choose EV if the situation is dire.

 

Unfortunately the reporting of information on here often turns into personal attacks. When I first started reading Bob's information, I simply took it as an experiment he ran, found something different and told us about it. Was it a flaw or intentional, If intentional why didn't Toyota tell us about it. Why does Toyota not tells us about anything? I'm certainly not understanding the somewhat frequent attacks on Bob about all this.

I don't plan on running out of gas (again) but as many of you mentioned there will be times a car stops and it's not necessarily a fuel issue. It would be nice to be able to limp over to the side of the road. Am I worried? No. Do I wish Toyota fixes this? Yes. If they do though it will take time. That will give us a lot of opportunity to hammer on each other. I'm pretty sure Toyota is listening.

 

Seriously!

Mr Wilson was kind enough to let people here know that if you run out of fuel, you're in trouble with this car when, in theory and practice from past models, this shouldn't be the case. It's a step back.

What certain people here seem to not understand is IF the computer system EVEN THINKS that you ran out of fuel, say due to a failing sensor or malfunction, you're screwed.

People never think it'll happen to them...and then it does.

I'm scared sh&tless of flying...I'm a mechanical engineer with an aero degree. People never expect to go down in an aircraft....but it happens. Let's hope it never does.

 

Efusco, you may well be right. Perhaps something was simply missed in the programing and can simply be updated. I actually would agree that is the most likely reason I have heard so far.
The other ideas I proposed were simply what I saw as possibilities. I don't know the details about what complaints Toyota has had, or what expenses they have had.
How damaging is it to the battery if it is run down to nothing?
There are many places in my area where I have seen people driving very agressively around folks driving under 20mph on the shoulder. They get agravated and drive that way. When this is a full width shoulder, not to big a deal. When it is a half shoulder, cars need to move around just a bit. If done carefully, not a big deal. If the driver is agravated...

I do agree with the 'wouldn't it be nice' aspect. And the information regarding the behavior of the new model and the numbers is FANTASTIC. I thank bob for that info.
Where I disagree is that this is a life or death issue equivalent to getting into accidents without seatbelts.
Sure, there have been incidents of people getting in accidents because of running out of gas in bad places. There have also been many more incidents of accidents due to high speeds. Should we have limit all cars to 35mph? That would prevent far more deaths in my opinion than this hubbub about the running out of gas thing.
No matter what the car's method of motion is, there will always be accidents. Minimizing those is important, but priorities are needed.

 

#1 Stabill will keep the gallon of gas good for one year.
#2. The extra gallon tank would be gravity fed to the main tank. You go back to the cargo area and turn a spigot if you wanted it mechanical. Keep it simple.

The real problem with relying on EV mode is that it is only good for one mile. It may or may not even get you off the road. A mile down the freeway is of little use.

 

The problem with this theory is that Toyota already controls the response available from the battery when you press the go pedal. There is no reason that they should not be able to allow some EV mode without allowing such a high amp draw that it damages the battery.

Seriously, from what I've gathered at PC a mountain climb is likely to be harder on the battery than the out of fuel situation. 1/4 mile runs are probably hard on it too... Yet, Toyota has not yet decided to shut down the car when you approach too steep a grade.

 

That's great to know! And you will live forever because you don't take any unnecessary risks and wear your seat belt. Time to cancel the insurance as it is just a waste of money.

Care to share the lotto numbers with me, because my crystal ball is out of calibration at the moment...

 

Only 50 miles? The Pacific Northwest has (or had) much longer gasless stretches than that.

Considering that those most prone to run dry are also prone to get much less than 50 mpg, and more prone to not know whether or not they've passed the midpoint of the 100+ mile gasless stretches (are my biases showing?), the reserve tank should be a bit larger.

 

i assume you are trying for a laugh and don't actually equate the aging process, ending in death, with the process of using gas and running out at the end?

yes i will die someday. everybody who has ever lived, except those alive today, has died. it's a pretty sure bet.

i am pretty sure i won't run out of gas though. pretty sure. can't say 100% - that would be silly of me. but yes, pretty sure.

 

Thankyou Rick, for returning us to the tenor of Bob's original post, from the trackless deserts that some have ventured to in this thread.

I too have Qs for Bob on this issue:

1. In the original versions of the Prius, G1 and G2, when all of the fuel was consumed in your experiments, was the SOC for the Traction Battery simultaneously down to the level at which, under normal conditions, the ICE would have kicked in to re-generate charge?

2. In your experiments so far with the G3 Prius, does a parallel situation occur? That is, the HV battery reaches a state of simultaneous SOC at which point the ICE would (if gas were present) kick in to re-charge the HV battery. I recall you indicated that there were 2 bars remaining on the SOC indicator. I assume then that this corresponds to the minimum SOC Toyota wants to allow. But did the car actually run out of fuel at a higher SOC?

One way to check would be to see what happens when operating under the EV-only mode when plenty of gas is present, and noting when the ICE kicks in.