If the engine is not turning, why power off while refueling?

hycamguy07 · 05-14-2007, 01:06 PM

<div class='quotetop'>QUOTE(Presto @ May 14 2007, 12:43 PM) [snapback]441722[/snapback]</div>

Quote:

I rarely shut my car off for refueling purposes. Usually, I'll just turn on EV, and start filling up. Doesn't matter if it's full or self serve. I don't like turning off the car since my carputer would have to reboot, and I don't feel like having to wait for it.
[/b]

Boy I could follow you around everytime you filled up and make the monthly quotaes..... LOL

Earthling · 05-14-2007, 01:10 PM

<div class='quotetop'>QUOTE(ystasino @ May 14 2007, 02:01 AM) [snapback]441487[/snapback]</div>

Quote:

If the engine is not turning, is there a reason (and I mean reason) to power off while refueling?

Thanks
[/b]

Because the sticker near the pump says that it is illegal to refuel while your motor is running, and your motor may come back on unless the power is off.

It's a matter of obeying a law that is there to protect you (and me).

Harry

Ichabod · 05-14-2007, 01:26 PM

Aside from the risks already mentioned here, I don't see any good reason to leave the car turned on while refueling. Here are my guesses why someone might want to do such a foolish thing:

1. To get in and out quicker... It really doesn't take that long to hit the power button though, so that's a bust.

2. To keep the car warmed up and not have to go through the warmup cycle again and hence lose some FE points... Since the it's most likely you're not in the station long enough for your car to really get cold, I don't think this is a good reason. And I defy you to show me a significant MPG hit by that one startup you might have saved yourself.

3. To keep a nice consumption graph going... If you really care about persistent data on your driving, get yourself a CAN-view.

If you can prove to your government that there's no chance of the engine starting while you fuel, and that there's no increased risk of static discharge due to electrical systems being turned on, then by all means, get the law changed. Until then, post your photo and license plate here so we all know to take cover when you're fueling.

qbee42 · 05-14-2007, 01:29 PM

<div class='quotetop'>QUOTE(Earthling @ May 14 2007, 01:10 PM) [snapback]441746[/snapback]</div>

Quote:

Because the sticker near the pump says that it is illegal to refuel while your motor is running, and your motor may come back on unless the power is off.

It's a matter of obeying a law that is there to protect you (and me).

Harry
[/b]

Some of the stickers in our area say that we have to "...remain with the vehicle and in view of the nozzle." I could never understand how the nozzle could see me in the first place, let alone after I shove its head down the filler pipe. I try to follow the law, but I'm not sure how to do it in this case. Perhaps someone from Michigan can explain this to me.

Tom

Darwood · 05-14-2007, 01:41 PM

As long as your SOC is aove half and you turn off your AC/heat, there is no reason the motor will start up. Rebooting does take a hit, albeit a small one. If my next stop is through the parking lot to another store (as it often is), the engine will run the whole time for no reason. If I leave it on, I can EV that 1/4 of a mile.

BTW, the law says the ENGINE must be off. If I don't power down, but ensure the engine does not need to start, I don't think I'm breaking any laws. The only time I will power down is if my kids are in the car or I'm in a bad neighborhood and have to go inside to pay.

ystasino · 05-14-2007, 02:07 PM

I don't really want a lecture. The EV button makes sure that the engine will NOT come on while refueling. I don't really think it's worth trying this myself but I want to know if there is any realistic reasoning behind it.

I am asking for mechanical reasons (not poetic ones) and I would appreciate if someone who is technically inclined answered this question.

Thanks,
Yiannis

Presto · 05-14-2007, 02:18 PM

^^^
A lot of times I won't even bother with EV since I know the car is warmed up and won't start. I haven't had the ICE start on me while I was filling. The weather is warmer now so that will help as well.

Ichabod · 05-14-2007, 02:25 PM

I was under the impression that the answer was already posted:

* Risk of static discharge is increased by a running engine (even if you trust yourself to "ensure" your engine doesn't start, do you trust everyone else? I don't).

* Risk of static discharge increased by active electrical systems.

I think the point of the law is not that you WILL blow up if you don't do as they say, but that you increase the risk. The video linked above is enough for me to say "yeah, it's worth reducing that risk, even if it's a very slim risk to begin with."

If you want hard numbers of static discharge in various operating modes, or statistics about Priuses catching fire at gas stations, I think that may be hard to come up with.

If you did want a poetic reason, which I know you said you didn't, my answer in Haiku form would be:

Power is always on,
Prius eagerly ingests.
Woofer booms, car too.

daveleeprius · 05-14-2007, 02:42 PM

<div class='quotetop'>QUOTE(Angel Flight Pilot @ May 14 2007, 12:00 PM) [snapback]441737[/snapback]</div>

Quote:

I'm a flight instructor. The protocol for fueling airplanes is to have ALL potential sources of electrical power turned off, and, obviously, the engine as well (wouldn't do to slice the fuel guy up in the prop). Static electricity builds up in the fuel hoses due to the rapid movement of gasoline. There is a remote chance of a static discharge spark where the fuel nozzle meets the metal of the airplane, right over the gas tank. You can imagine the potential consequences of that.

[/b]

My friends dad worked for Northwest Airlines in the 1960s-80s and he was in DaNang and had to refuel a Boeing 720B with no ground power unit. Interesting to say the least! They had to leave one engine running.

Dave

jamarimutt · 05-14-2007, 04:35 PM

If I am alone, I turn the car off when refueling. If someone else is in the car I press P and leave the system on (doors locked) so that the air conditioner continues to operate.

Around here it's against the law to use a cell phone while refueling a car, although that myth has been debunked (most recently by the mythbusters). It's also illegal to run a red light, but I regularly do it in dark intersections. And, it's illegal to speed, and who does not do it once in a while?

05-14-2007, 01:26 PM	#13
Ichabod Artist In Residence Join Date: Jul 2006 Location: Newton, MA Posts: 1,774 My Car: 2006 Prius Package: #7 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 7	Aside from the risks already mentioned here, I don't see any good reason to leave the car turned on while refueling. Here are my guesses why someone might want to do such a foolish thing: 1. To get in and out quicker... It really doesn't take that long to hit the power button though, so that's a bust. 2. To keep the car warmed up and not have to go through the warmup cycle again and hence lose some FE points... Since the it's most likely you're not in the station long enough for your car to really get cold, I don't think this is a good reason. And I defy you to show me a significant MPG hit by that one startup you might have saved yourself. 3. To keep a nice consumption graph going... If you really care about persistent data on your driving, get yourself a CAN-view. If you can prove to your government that there's no chance of the engine starting while you fuel, and that there's no increased risk of static discharge due to electrical systems being turned on, then by all means, get the law changed. Until then, post your photo and license plate here so we all know to take cover when you're fueling. __________________ 2006 Barcelona Red Metallic - a.k.a. "The Professor" :: Accessories/Mods :: BT Tech Stiffening Plate - Engine Block Heater - OEM EV button - OEM Mud guards - Rear Bumper Protector :: Near-future :: ScangaugeII

05-14-2007, 01:41 PM	#15
Darwood Senior Member Join Date: Feb 2005 Location: Minnesota Posts: 1,480 My Car: 2008 Prius Package: #2 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 1	As long as your SOC is aove half and you turn off your AC/heat, there is no reason the motor will start up. Rebooting does take a hit, albeit a small one. If my next stop is through the parking lot to another store (as it often is), the engine will run the whole time for no reason. If I leave it on, I can EV that 1/4 of a mile. BTW, the law says the ENGINE must be off. If I don't power down, but ensure the engine does not need to start, I don't think I'm breaking any laws. The only time I will power down is if my kids are in the car or I'm in a bad neighborhood and have to go inside to pay. __________________ _____________________________________ ......My other car is a Prius too!......

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05-14-2007, 02:07 PM	#16
ystasino Senior Member Join Date: Apr 2007 Posts: 370 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	I don't really want a lecture. The EV button makes sure that the engine will NOT come on while refueling. I don't really think it's worth trying this myself but I want to know if there is any realistic reasoning behind it. I am asking for mechanical reasons (not poetic ones) and I would appreciate if someone who is technically inclined answered this question. Thanks, Yiannis

05-14-2007, 02:18 PM	#17
Presto Has his homepage set to PC Join Date: Mar 2005 Location: Vancouver, BC Posts: 1,158 My Car: 2005 Prius Package: B Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 3	^^^ A lot of times I won't even bother with EV since I know the car is warmed up and won't start. I haven't had the ICE start on me while I was filling. The weather is warmer now so that will help as well.

05-14-2007, 02:25 PM	#18
Ichabod Artist In Residence Join Date: Jul 2006 Location: Newton, MA Posts: 1,774 My Car: 2006 Prius Package: #7 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 7	I was under the impression that the answer was already posted: * Risk of static discharge is increased by a running engine (even if you trust yourself to "ensure" your engine doesn't start, do you trust everyone else? I don't). * Risk of static discharge increased by active electrical systems. I think the point of the law is not that you WILL blow up if you don't do as they say, but that you increase the risk. The video linked above is enough for me to say "yeah, it's worth reducing that risk, even if it's a very slim risk to begin with." If you want hard numbers of static discharge in various operating modes, or statistics about Priuses catching fire at gas stations, I think that may be hard to come up with. If you did want a poetic reason, which I know you said you didn't, my answer in Haiku form would be: Power is always on, Prius eagerly ingests. Woofer booms, car too.

05-14-2007, 04:35 PM	#20
jamarimutt Join Date: May 2004 Posts: 972 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	If I am alone, I turn the car off when refueling. If someone else is in the car I press P and leave the system on (doors locked) so that the air conditioner continues to operate. Around here it's against the law to use a cell phone while refueling a car, although that myth has been debunked (most recently by the mythbusters). It's also illegal to run a red light, but I regularly do it in dark intersections. And, it's illegal to speed, and who does not do it once in a while?