driven 128 miles on Empty

There is so much misinformation in this thread it is difficult to know where to start. But I would like the documentation from the Gen 2 Prius manual where it states that the tank should be refilled when it reaches 4 bars. I have also NEVER heard of any "long term cracking of the fuel tank bladder" if it is left near 0 or 1 bars. I have heard that the bladder may "contract" and be difficult to re-expand back to the full size, but eventually it does. If the bladder wasn't flexible it couldn't be used for the purpose it was intended for. I have been regularly taking both Prius down to 0 or 1 bars for 6 years, without problems (at least so far).

Then there is the absolute death and destruction of your Prius when you run out of fuel. The fuel pump fries, replace the tank because you can't replace just the fuel pump, replace the main battery because it was depleted driving wtihout gas. Once again, I haven't read about any fuel pumps failing because of this, and as far as I know, you can't deplete the battery driving it while out of gas, only if you leave it in N. When driving without fuel, eventually the Prius shifted itself into N, at which point I coasted to a stop and turned the car off.

I have run out of gas in the Prius twice. Both times the car survived. Both times I drove it absolutely as far as it would go on the main battery, and both times after putting gas in I was able to start it. On the second time, I drove for several miles on my newly installed that day Hymotion battery, and it came to a complete stop just feet from a gas pump. It wouldn't start after putting in just one gallon, not even after putting in three gallons. I finally had to disconnect the negative connection of the 12V battery, and after that it was fine. I think the problem was that I only put in a gallon and tried to start it a couple of times. I think if I had put in four or five gallons and then tried to start it the problem would have been avoided. If I ever run out of gas again I'll try this theory.

The people who designed the Prius would not allow the car to destroy itself, even though the driver might want to go beyond what is reasonable.

 

+1 ^

 

Adding to sub3marathonman comment:
The cause of all this misinterpretations and wrong judgments it's because of an abrupt number of Prius owners with out a reputable education on the mater.
Anybody can comment in everything, including certain BS....

 

Why let the truth get in the way of a good posting. Did you go to a Toyota Prius training school? I think that most users on this forum are not Toyota technicians and read this forum to gain knowledge and find new ideas about their Prius and most users can sift out the BS. One users interpretation is just their own opinion whether it is a bad judgement or not it is still just their opinion.

 

OK, so everything is "just their own opinion?" The previous statement from lopezjm2001 was "The Gen2 Prius manual states that you should keep refilling the gas tank as soon as it reaches a low 4 bars." That is more than a statement of opinion, it is a statement of an alleged "fact." I am merely stating, quote the Gen2 Prius manual. Otherwise the statement is incorrect and should be corrected. So which is it?

 

We have to look at the definition of "empty" Is it when the distance to empty reached 0? Is it when the last pip starts flashing? Is it the fuel tank has no fluid and using the residual fuel on the fuel line? Stefano's 128 mile equals 65 miles for those without PHEV. Any Prius can easily handle 65 miles pass the 0 DTE. Now, if he has truely ran out of gas and drove 128 miles, that means the 128 miles is driven electrically, difficult to do but not impossible. But, I doubt that's the case with him. His empty probably means that when the DTE has reached 0. I think he could have gone another 50 to 100 miles before he ran out of gas.

 

So to stefano5777, he didn't reach "empty" as in out of gas, just "empty" as in the odds of running out of gas are so high at this point that I'm not going to risk going any further. And I would agree, that is definitely very impressive driving and usage of the 4kw Enginer kit.

Also, I don't know about later Gen2 Prius, but in the 2006 it will go a maximum of 24 miles before running out of gas, and one time to 22 miles. I can verify those two data points. And even refilling from empty, I don't think that I've ever gone over 11 gallons.

 

First time here folks. Have a 2005 and a 2006 Prius.

The 2005 continued to run when the last digit flashed and vanished. I mean, why not, it shows fuel in the tank right, just like every other fuel gage for my last 50 years driving!

The 2006, first month ran out of fuel twice, on the highway, shortly after the flashing or idiot warning light (whatever it was as I have not been below 1/4 tank "indicated" since in either vehicle). No apparent ill effects on the 2006.

Two different service managers said "running out of fuel with fuel still indicated is normal" Of course my argument was, Toyota did not take "human factors" into consideration letting a vehicle out that quits with fuel still indicated or worse, presents you with a warning (flashing or idiot light) then quits on almost immediately on the freeway before you get to the next available exit/gas station.

At minimum, shouldn't there be, if the rule is, "never below 1/4 tank" a warning something like "Fuel immediately" at 1/4 tank? Build an unmistakable margin into the warning. NOT this issue-a-warning , then quit in 5 miles like it got my wife, then me (after I yelled at her, ahem)

I am a retired airline pilot. A system like this would never pass the FAA certification process. WE, you and I, now know there's ambiguity in this whole Prius "guessgage" game, but how about unsuspecting drivers who are used to having some fuel even with the gage shows zero? Never in my life has a car quit for fuel exhaustion with fuel indicated in the tank. Cheers

 

Are there many automotive designs or features that will pass this certification process?

The very first tank of 'my' first car, a 1970's era Ford, did.

Subsequent cars have had significant fuel capacity below the 'E' mark. One, a pre-hybrid still in the household, has 27-30% of its fuel capacity below 'E'. How many pilots would tolerate the weight penalty of that sort of gauging sloppiness?

PS: for those who can't understand why anyone doesn't automatically refill at the 1/4 mark, I have been characterizing my fuel gauges ever since a bad experience with predatory pricing decades ago, when most stations along my route did not keep holiday hours. The open station demanded a steep fee merely to unlock the pump, and that fee could not be split with the other customer who walked in at the same time. The next station known with certainty to be open, was 135 miles down my route, half the range of that short-range car. The fuel needle was slightly below half a tank.

I made it. Fuel range has been a critical point ever since.

 

After having a quick flick through the manual ( always a first time for everything lol ) I found the reference that Lopez mentioned, on page 92. Heavy emphasis on: "It is a good idea" to keep the tank over 1/4 full... See pic below.

I regularly drive my Prius 50km - 70km after the last brick blinks, which always manages to have 2 - 4 litres left when I fill up at that point. It always impresses me as to how accurate that this gauge is.

If I remember correctly, the moment the last brick blinks, you should have approx 4 - 5 litres of fuel left, which really isn't any reason to get gauge anxiety over, if a conventional fuel tank/ fuel sender set up is employed. Bladder installed cars in the US however, are likely to have a situation where no two Prius fuel gauges at close to empty, behave the same way, so I can sympathise that the bladder system is a PITA.

​

 

I looked thru the 2008 manual and found two errors:
1. The car must be towed with the rear wheels off the ground
2. During the 602 mile break-in you should not drive for excessive distances using the lower gears.

 

Now THAT'S being tricky.

Instead of another post stating he was wrong, or even stating in the edited post about being wrong about refilling at 4 bars, and being wrong about throwing out some ridiculous theory about how, quoting the original lopezjm2001 posting, "the Repetitive emptying of tank to near 1 or 0 bars can cause long term cracking of the fuel tank bladder. Then the bladder would have to be replaced which would be very expensive," instead the entire post is changed without comment. Which then confuses people reading subsequent postings which quote the original lopezjm2001 post.

 

The numbers are interesting, though have little relevance to real-world driving...with similar recharges, using every drop, and flat terrain many PHEV's would be in this range.

 

IMO...

But IMO it's someones personal property. I suppose if for whatever reason you want to run your vehicle as low as possible then you can....

But I think when giving a "recommendation" for the general public or average driver, not obssesed with obtaining high MPG tank numbers...you have to recommend not pushing to empty (as Toyota recommends).

Not because running to empty may or may not result in catastrophic failure, or immense damage or nothing more than pulling over to the side of the road and filling up with a carried gallon of gas.

It's because for the majority of people? Running out of fuel...and you never know when exactly it's going to happen...is simply not a good idea and somewhat dangerous.

I guess I can understand the curiosity, but it seems like totally unnecessary risk and a "game like" endevour.

At that point? Your vehicle becomes less an automobile and more a giant Toy inwhich you are playing an unnecessary game with...

Personally my opinion...but I wouldn't do it...even if you can...

 

Do car manufacturers recommend adding turbos, superchargers, nitrous, struct brace, + size rims? No they don't but people do it. Infact more people do any of those things than all of Prii combined in the world. There are more 9 second Hondas than I can count. Hell, there are more Engine mod manufacturers than Enginer owners. All those people who added turbos and superchargers, and nitrouses to their cars are going to push their cars to the limit. What do you think a Prius PHEV owner's gonna do?

 

After thinking about this, I would have to disagree.

First, it is a "real-world driving" report from stefano5777. Now, it is true that other PHEV's would be in this range, I am usually able to go 1200 miles on a tank with a little over 8 gallons refill, that is with a Hymotion kit, which costs almost 3x as much and also has 1kw battery more. So to drive a 4kw Enginer kit so efficiently is definitely a testament to stefano5777's driving skill. Even with an essentially flat route it would be difficult. Now, if we find out that he drives half a mile down a private road from his house to his office using an EV switch, that might change things a bit.

 

I've never run out of gas. But while experimenting with PHEV stuff, many times I have pulled the relay to the fuel pump on a Gen-1 Prius. The engine sputters for a moment and dies, followed by a pure EV mode. Once re-enabling the fuel pump, it starts right up. So I'd say no damage to the engine or fuel injectors. But obviously this experiment doesn't address possible issues with the fuel pump and gas tank actually being out of gas.