800 mile attempt on one tank

[bestmapman]

Originally Posted by a64pilot

I don't know, from some of his fuel consumption pictures, I would say he could easily do it. I don't think it would be impossible to do, I think 80 MPG would do it, I just don't have the commute that that is mileage friendly. I think it would take P&G to do it and I don't have the patience or the lack of traffic. Lately it's been 4 to 6 miles several times a day with at least an hour between trips and it's hard to keep the mileage up. I can't get the first 5 min. segment above maybe 50, and it's hard to average 68 or better if you drive is only 8 or 10 min., but given the desire etc.
Oh and I doubt the Japanese Prius would have a bigger tank, if nothing else why would they want the extra weight?

I did a 1000 tank in the Gen II, but have not attempted one in the Gen III

[DrJon]

So..... Tell us the mileage when you get the beep and first flashing!!

[a64pilot]

Originally Posted by DrJon

So..... Tell us the mileage when you get the beep and first flashing!!

Yesterday at 743, but then it went away for a while but was back by 750 and has been flashing since then, so I'm calling it 743. I'm a little over 800 now, happened on the way to work this morning. I am travelling with exactly one US gallon in a spare tank with funnel so I can get every drop out of it. Oh and the flashing pip started with about 20 miles left to go on the DTE? I assume the flashing pip is not triggered by the DTE getting to 0? DTE is computed by what I don't know, it doesn't seem to come from past mileage performance, but I guess it has to be pessimistic or there would be great cries about not getting the mileage they were promised by the DTE?

[qbee42]

I was also under the impression that the 2010 will stop dead when it runs out of gas. There was quite a thread about it a while ago, with much finger pointing and gnashing of teeth.

Is one gallon enough to restart a 2010? I would be worried about that.

Tom

[bwilson4web]

Originally Posted by a64pilot

Yesterday at 743, but then it went away for a while but was back by 750 and has been flashing since then, so I'm calling it 743. I'm a little over 800 now, happened on the way to work this morning. I am travelling with exactly one US gallon in a spare tank with funnel so I can get every drop out of it. Oh and the flashing pip started with about 20 miles left to go on the DTE? I assume the flashing pip is not triggered by the DTE getting to 0? DTE is computed by what I don't know, it doesn't seem to come from past mileage performance, but I guess it has to be pessimistic or there would be great cries about not getting the mileage they were promised by the DTE?

You've got an 800 mile tank 'in the bag.' <GRINS>

Bob Wilson

[Prius 07]

Originally Posted by a64pilot

Somebody will get a 1,000 mile tank, maybe somebody already has.

FYI diamondlarry had a number of >1000 mile tanks with his 2007 genII. Nevertheless 800 is a great achievement - congrats!
Driving Past The Add More Fuel Beep

You may find his posts useful in terms of technique and MPG accomplishments.

[bwilson4web]

Hi Tom,

Originally Posted by qbee42

I was also under the impression that the 2010 will stop dead when it runs out of gas. . . .

What happens is this:

• engine finally runs out of gas - there is no "check engine" light or other indication that the last of the gas was consumed
• car switches to traction battery power - unless you are watching the energy display or monitoring the traction battery SOC bars, you can't tell
• traction battery reaches ~2-3 bars and throws "electronic steering" light and stops providing power - this is the really strange part that still no "check engine" light and a steering error is shown. But as soon as it stops providing traction battery power, the car only coasts. There is no way to get the car to move another foot to a safer place to park.

My fuel exhaustion tests were:

1. On a down grade and "electronic steering" light came on. I coasted into the parking lot at a park; added the 1 gallon; and started right up; and drove to gas station to fill-up.
2. On an up grade at 3:00 AM and "electronic steering" light came on. I applied the accelerator and first learned there was nothing. I still had momentum and coasted into a parking lot to add the spare gallon.
3. Making a "U turn" on I-565 where I'd been running 70 mph to run out the gas. As I turned onto the 'on ramp' and applied the accelerator, the car was sluggish and I then noticed the traction battery SOC was down one bar. However, I had traction battery power, still. I went down the "on ramp" and pulled on the shoulder and using the traction battery, went another 200 yards to be away from "on ramp" traffic. I didn't see the "electronic steering" light and still had at least 4-5 bars on the SOC indicator. I added the spare gallon and proceeded to the gas station.

With the maintenance manual, I can find the wire that powers the electronic fuel pump. I'll put in a current 'shunt' and record the current for the next fuel exhaustion test. When the fuel pump runs out of gas, it should 'spin' and the reverse EMF cut the current flow. I can then engineer a circuit with an "OUT OF FUEL" indicator.

Bob Wilson

[DrJon]

Originally Posted by a64pilot

Yesterday at 743, but then it went away for a while but was back by 750 and has been flashing since then, so I'm calling it 743. I'm a little over 800 now, happened on the way to work this morning. I am travelling with exactly one US gallon in a spare tank with funnel so I can get every drop out of it. Oh and the flashing pip started with about 20 miles left to go on the DTE? I assume the flashing pip is not triggered by the DTE getting to 0? DTE is computed by what I don't know, it doesn't seem to come from past mileage performance, but I guess it has to be pessimistic or there would be great cries about not getting the mileage they were promised by the DTE?

What does Trip A say for MPG? Maybe you can make 900.

[a64pilot]

Originally Posted by DrJon

What does Trip A say for MPG? Maybe you can make 900.

68.1, I don't think so. I assume that's really only about 64 MPG or so? 64 x 12.5 = 800. I think there must be more than 12.5 gl. usable or I would have run out by now. I based my attempt on 12.5 gl and 64 MPG
I could do better, this was on a whim as I would be the only driver for a while, and the wife won't play.
By 1000 mile tank, I meant Gen III. I'm sure it's been done on the Gen II. Pretty sure it had been done by somebody on a Gen III.

The only thing that had me real worried if it was possible to discharge the traction battery enough so that a re-start wan't possible. Seems from Bob's description, unless I'm stupid, that won't be a problem.
Bob have you "topped it off" to see how much usable fuel capacity there is?

[bwilson4web]

Originally Posted by a64pilot

. . .
Bob have you "topped it off" to see how much usable fuel capacity there is?

My three fuel exhaustion events showed 12.1 gallons. So working it backwards:

800 / 12.1 = 66.2 MPG (true)
69.4 MPG indicated (using 5%)

Bob Wilson