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tmahfan117 t1_ixszeug wrote

It doesn’t, mostly.

You can totally pump gas into a car with the engine running and not have anything explode. As long as the gasoline doesn’t get to the engine or any other part hot enough to ignite it, it won’t explode.

The problem is that people In general are stupid, so removing every possible risk is the best move.

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HeadBat6660 t1_ixtp2dg wrote

This.

The same reason why some countries put warning stickers on microwaves that says "Do not put babies in the microwave"

Stupid people are gonna stupid.

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tdyo t1_ixtq6qg wrote

Mama says stupid is as stupid does.

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_-Event-Horizon-_ t1_ixtyuy8 wrote

>Mama says stupid is as stupid does.

Hey, I heard you invested in some sort of a fruit company, how is it working out for you?

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Tardis80 t1_ixtsqjm wrote

Now I want to now which countries need these stickers. I think USA but anybody else?

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Tupcek t1_ixtvi9q wrote

in almost all the countries if you brought this up to court, you would get laughed at all the way there and back and probably the rest of your life.

Don’t know what it means, either that in US you could be sued for anything, which is bad because no common sense and it only serves the lawyers who can make a lot of it, or that it’s great system that takes every matter seriously. Pick your choice

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Mysticpoisen t1_ixu82j5 wrote

The US does not use them, as far as I can tell baby in microwave is not a warning label in any country.

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Catch_022 t1_ixtsof1 wrote

I remember watching an interview with a South African gangster who said that when he broke into a house and the people there didn’t get what he wanted, he would put the baby in a microwave as an ‘example’.

I hope he was joking.

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limt__ t1_ixtx4ir wrote

*oven

I'm not gonna lie, he seemed kind of serious.

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Equrteadt t1_ixtr74e wrote

now imagine everyone leaving their car on when filling up? that'd be a huge waste of fuel overall.

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Charles_Whitman t1_ixt3hxs wrote

I don’t have a reference for this, but I was told by my father that it dates back to the days when filling stations pumped gas for you and it was to help stop people from accidentally driving off before the pump jockey was finished. They didn’t have pop-off hoses then either, so driving off with the hose still in the filler hole could do damage all around.

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Quietm02 t1_ixttml4 wrote

That may be a part of it, but it's definitely mainly safety. Even countries where people have always done their own fuel have the rule.

Car engines are hot and are obvious ignition sources. During normal operation the fuel is nicely contained and that's fine. When refuelling the fuel is not nicely contained and can spill. This is an explosion risk.

Its a very small risk admittedly, but still present.

I'm not aware of any incidents at fuelling stations (though am sure there are some) but am very aware of industrial accidents where trucks have left their engine on around hazardous materials and caused an explosion. I'm sure there was a very serious one in Texas in early 2000s.

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FattestSpiderman t1_ixtq16u wrote

I was told the same! Considering the utterly moronic things you see people do on a day to day basis, it wouldn’t surprise me if it was a daily occurrence for fuel stations back then

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nuclearrwessels t1_ixtrn9s wrote

I used to go the a full service gas station every week across from my job for a fill up. The attendant hit on me every single time. One day, I was distracted on a Bluetooth phone call and just started to drive away while he was mid pump. I stopped and thankfully nothing got damaged but I was too mortified to go back for weeks.

I finally went back one day and he goes “ahhh, hello! Very beautiful, not very smart.” Lmaoo i was like yah fair play.

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BSC25M t1_ixtwt70 wrote

Manage a full serve station…It’s STILL a fairly common occurrence…Literally happened yesterday…

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AutoRedux t1_ixtwryc wrote

Still is today. Especially at truck stops.

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dont-YOLO-ragequit t1_ixt37mc wrote

Also not mentioned is that the evap system could sense a leak and make a check engine if it runs with no vacuum.

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Scizmz t1_ixtqk4g wrote

This is actually a thing. It can trigger a CEL if left running when you pop the gas cap.

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tiedyemike8 t1_ixt5tz0 wrote

Many early cars had the gas tank right at the base of the windshield, above the engine. You can imagine the risk of fire if fuel was spilled on top of a running engine.

Cars can backfire at idle, possibly sending embers out the exhaust, a spill while filling a tank can put fuel on the ground, the fuel vapor that rapidly develops can be ignited by hot soot particles if the engine backfired.

These things are not much of an issue nowadays, but fuel spills still create a serious hazard and it's definitely safer to turn vehicles off for this reason.

For the last 40 years or so, vehicles have had sealed fuel systems for fuel vapor control. An emissions system. If the car is running while fueling, the system will detect a leak and a check engine, ses light will be illuminated.

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kyrsjo t1_ixu1fuj wrote

Oh, yeah. I have a picture of myself refilling a Trabant (old Soviet car), the tank was inside the engine bay, on top of the (hot) engine.

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cosmoboy t1_ixt0i62 wrote

Besides what's already posted, I'd think with a running car you would have a better chance of accidentally taking off with the hose.

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iblastoff t1_ixto1xd wrote

do you have to? probably not. but i think the obvious answer is unless you're driving some ancient car, turning off your vehicle is literally gonna save you on gas since you're not wasting it idling for 5 minutes or however long it takes to fill up.

now imagine everyone leaving their car on when filling up? that'd be a huge waste of fuel overall.

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mythic_device t1_ixtq8up wrote

Yes. With most new cars like hybrids that shut the engine off automatically at red lights, it makes no sense to leave an engine on during 5 minutes of fuelling and paying.

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Scott_4560 t1_ixtqu0j wrote

One of the dumbest features of modern cars. Would rather spend a few dollars on fuel wasted while idling than fork out for a new starter motor ever few years

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happygoclunky t1_ixts45w wrote

Also saves on emissions and polutuon in cities and towns, improving people's health.

I have a car with this feature and after 8 years the starter is still going strong. And you can turn the auto stop off

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iamnogoodatthis t1_ixtspe0 wrote

Maybe you need to buy cars with less shitty starter motors. My 2013 stop-start one is still going strong, and the lungs of people where I live are the happier for it.

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the1slyyy t1_ixtwy3v wrote

Pretty sure these stop starts designed their starters to handle the load

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kyrsjo t1_ixu1ofb wrote

Also, starting a warm engine doesn't take much, compared to i.e. a normal or especially a really cold start. To start my old diesel car when its say -20c and it's had time to get really cold, takes a while, even after bumping the glow plugs a few times.

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Squirrels_Gone_Wild t1_ixtvjt4 wrote

Not sure why no one has mentioned the idling thing yet. It's bad for the environment and wastes gas. Multiply that by the millions of cars on the road and it adds up.

According to this article, its 6 billion gallons of gas every year (half of which are "normal" cars, the other half being heavy duty stuff) https://www.bloomberg.com/news/features/2021-08-10/can-cities-finally-win-the-war-on-vehicle-idling and that's with almost no one idling at gas stations.

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Imaskeet t1_ixt9veu wrote

One reason I've heard is for at gas stations with attendants so that they are not breathing in so many fumes all day long.

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encogneeto t1_ixt3dfs wrote

You don’t^*

Where I am, gasoline and petrol are generally full service and they do not require or ask you to shut off your engine before filling your tank.

Contrast that with the full service LPG stations where they require you to turn off the engine to fill your tank even if your tank isn’t even connected to your vehicle.

^* Some restrictions apply. Please refer to local code for details.

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SocalGSC92 t1_ixtsasj wrote

When i visited Uganda, the gas stations all had signs saying “Do not turn off engine.” Everyone kept their car running. I just kinda took it as: well thats what they do here.

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aathas t1_ixtd1wx wrote

You're getting a ton of incorrect info here OP. The only reason to turn off the engine when fueling up is to avoid a check engine light coming on as the ECM can spot a large leak, ie your gas cap being off. Before OBD and emissions monitoring, you'd find plenty of people in the dead of winter fueling up with the engine running to keep the car warm.

The increased risk of fire from a spark is also bunk as fuel vapor exists whether or not the engine is on or off. It's why you don't smoke and why you should touch grounded metal before you fill up the tank.

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Frednotbob t1_ixtoeue wrote

I didn't know for sure, so I did a quick search:

>“It's is safest to shut off your vehicle to avoid a fire, static electricity or a check engine light,” says Lauren Fix, an ASE certified technician and sector analyst at The Car Coach. “The fire risk is that the fumes burn, not the liquid. This could lead to an explosion.”

>
>https://www.familyhandyman.com/article/can-i-pump-gas-with-my-car-on/#:~:text=%E2%80%9CIt's%20is%20safest%20to%20shut,could%20lead%20to%20an%20explosion.%E2%80%9D

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atomicmrpelly t1_ixtzr74 wrote

Never mind whether or not it's safer to switch the engine off, there is no need to leave the engine running, wasting fuel and belching CO2 and other pollutants into the atmosphere when the car is not going anywhere.

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revenantae t1_ixsz0i7 wrote

Because there is a possibility, no matter how small, that you might create a spark when the car is on. If that happens, there is a chance you might ignite a fire. That COULD cause an explosion, which could then cause a much larger explosion.

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DLBaker t1_ixtmeuk wrote

As an extra precaution I advised my children to always place a hand on the car before inserting the hose to discharge any possible static through your hand and not at the fuel inlet.

It follows the same principle as attaching a grounding cable to an aircraft prior to fueling.

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logan0921 OP t1_ixt0u40 wrote

Yeah but what about the car being on increases the chance of a spark by the gas tank? I can understand sparks cause from static, or smoking while filling up, etc

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KrustyBoomer t1_ixt1cj3 wrote

Much of the car is grounded back to the battery negative. Spark could happen anywhere then. Also not supposed to get in and out of the car to stay warm too. Higher chance generating static in winter

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[deleted] t1_ixt22k4 wrote

[deleted]

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nesquikchocolate t1_ixtjnl8 wrote

That's a falacy, though. You can't prove a negative like that.

Even if only 1 fire/explosion/loss of life occured due to possibly running the engine while refuelling, that sign could have helped.

There's no downside to the refueling station for posting that sign.

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[deleted] t1_ixtz60h wrote

[deleted]

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nesquikchocolate t1_ixtzedh wrote

Like I said, can't prove a negative that way..

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[deleted] t1_ixtzi76 wrote

[deleted]

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nesquikchocolate t1_ixu056o wrote

Except that your entire position depends on using Google to not find some obscure hand-written news article about a 93 year old ford that caught fire at a refuelling station.

Your assumption is that all incidents are listed on the Internet and easily searchable using common terms - which is absolutely false in any event. Not every town has a news reporter that documents every occurance in a public facing repository.

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[deleted] t1_ixu0h9l wrote

[deleted]

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KrustyBoomer t1_ixu93gc wrote

For 100-years, NO ONE ever turned their cars off typically to fuel, for sure after self-pay became the norm. I think part of today's worry is how hot catalytics get and could ignite vapors. Probably still hot though.

This one is the classic static spark though, getting back in the car error I pointed out. Forward to end, lot of filler.

https://www.youtube.com/watch?v=T6VKxmUPb3g

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nesquikchocolate t1_ixu27r4 wrote

Let me help you quickly with this postulation.

I postulate that the sign stating your engine must be off during refueling exists. I also postulate that because this sign exists, an incident with refuelling was prevented. Prove I'm wrong?

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[deleted] t1_ixvbxi6 wrote

[deleted]

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nesquikchocolate t1_ixvh8s1 wrote

But obviously you do need help with it, because it's been bothering you enough to come back and continue talking nonsense.

My argument was not whether the hazard is present or not, just that your statement doesn't hold water logically. But you seem to have missed that, again.

You cannot reason that "lack of proof" is "proof to the contrary".

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[deleted] t1_ixvhp6j wrote

[deleted]

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Sea-Preparation-5528 t1_iy2hbyn wrote

What is this presumptive statement of “knowing ‘plenty of people,’” referring to? I’ve never seen anyone leave their car running while refueling. It’s seen as common sense out here to turn off your engine for safety reasons, whether that be the whole truth or not, for the reason to turn the engine off. How many people are “plenty?”

What are the statistics for how many people refuel with their engines running vs. how many refuel with their engines off? I’m guessing the latter would be the vast majority, and the former would likely be so minute, that it’s not surprising that there haven’t been any National stories of any incidents.

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popeshatt t1_ixtmedm wrote

The gas tank isn't normally open. The engine contains the gas inside, but fueling potentially introduces vapor to the space outside the engine where there could be a spark and the explosion wouldn't be controlled.

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aDvious1 t1_ixt7t6q wrote

But you do create a spark with the engine on. Around 1200 sparks/minute while it's idling.

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Scizmz t1_ixtqoj6 wrote

Electrical systems ground to the frame of the car. If there's a substantial difference in charge between the nozzle and the frame, sparks are possible, though unlikely. Most fueling systems are grounded out to prevent this.

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Tanthiel t1_ixte08l wrote

Also in the event of spark, you're sitting on top of thousands of gallon of combustible liquids.

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potentiallyasandwich t1_ixtpsof wrote

I had a wreck of a combo once that wouldn't start warm. Used to have to park it just outside the services, leave it running and fill it up with cans.

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davtruss t1_ixtscda wrote

There are days when I cannot express adequately the appreciation I feel for redditors and their take on things. Then there are days when I appreciate google more:

Pump Gas with Engine ON?

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Foxwolf00 t1_ixtta1f wrote

For the same reason capes have the label: "Warning: cape does not allow user to fly." Humans are morons, and we quit letting nature take its course in regard to morons.

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bakerzdosen t1_ixtxfwl wrote

A couple of decades ago when I was in high school, I had an old beater Chevy Cavalier. The starter died on it and my dad thought it important I change it myself (something I definitely agree with now.)

Except he saved a few bucks by buying a rebuilt one figuring it was fine as they had a lifetime warranty on them. We learned after I put in the 5th one why that warranty was so critical.

Point is: I never actually trusted that car to start. So I always parked on a hill and when I couldn’t, I left the engine running. So I probably filled that tank for two solid years with the engine running. There were occasionally signs but really, no one ever said a word to me. And I miraculously lived to tell the tale.

(Once we put in an OEM starter I never had a problem again.)

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unusualmusician t1_ixtz967 wrote

I live in Northern Alaska. It often stays below -30°F(-34°C) for weeks at a time, sometimes reaching below -55°F(-48°C). Rarely does anyone so their engine below 0°F (-17°C) here at the pumps.

I can see many reasons to do so, your vehicle is an easy theft target, wasting fuel, pollution, a super rare chance of combustion from fuel vapors, etc. But there is no definitive YOU HAVE TO moreso than why you can't legally cross the road when the red hand says you can't, even though you see no cars and it probably will be fine.

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CMG30 t1_ixtos4a wrote

The risk of fire is very low with the engine running or not. Slightly higher with the engine running, but not much.

I would imagine that the biggest reason is that it's simply bad practice to leave any machine on when you're away from the controls. A kid could knock the gear shift. A crook could jump in. Let your imagination run wild. Any manner of remote but real possibilities can be avoided by simply turning the thing off. Kind of like wearing a seatbelt. Most people never need it, but that one time they do makes all the difference...

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iamnogoodatthis t1_ixtsr8o wrote

Why do you want to keep it running? Think how unpleasant gas stations would be if everyone sat there idling.

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Dannybuoy77 t1_ixtu5b7 wrote

Large concentration of engines pumping out fumes in one place isn't a nice idea. Also you need to take your keys out when you go to pay to lock your car so it doesn't get stolen

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bmccooley t1_ixu0hpy wrote

Go to pay? I don't think I've gone into a station to pay in 20 years.

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Dannybuoy77 t1_ixu0pxo wrote

UK fuel stations are probably 80% pay inside. Some have chip and pin readers now but not many

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laz1b01 t1_ixtvigc wrote

You ever watch Die Hard (or similar movies) where there's a plane with a leaking fuel taking off, then Bruce Willis ignites the line of leaking gas, and you see it slowly going up in flames in a straight line towards the plane?

Yea...spoiler alert, it doesn't really happen. I learned the hard way. Gas is highly combustible, so it nearly goes up in flames in an instant, so the scene in movies is for cinematic effects.

So when you put gas in a car it goes to the gas tank. From the gas tank, goes to the engine where it's burned to make the car move. Fortunately, safety laws and design have put precautions to ensure that gas within the tank is not burned. But just because it's designed for safety, doesn't mean it's 100% full proof cause of design flaws. So you turning off your car is to ensure the burned gas in the engine doesn't reach the tank (which eventually reaches the gas pump)....because if it does reach it, it'll burn instantly.

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Any_Werewolf_3691 t1_ixtwo60 wrote

A lot of the pump restrictions relate to gas pump fires. In truth they didn't actually know what was causing it. Finally someone ran some statistical analysis on the events and discovered it was mostly women and in cold weather. Some observation showed women were significantly more likely to get back into the car in winter. Sliding into static covered seats in a car dried out by the heater, then sliding back out to grab the handle when tank was full. This caused static discharge.

Static discharge was the primary culprit. This is also why we switched to plastic gas cans.

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visualvector t1_ixtx1hn wrote

Is it as simple as not wanting those pumping gas to breathe exhaust fumes?

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raysqman t1_ixtxtzz wrote

Why wouldn't you? You're not using it to go anywhere.

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Psycheau t1_ixtyece wrote

It's what you can't see that you need to worry about. The vapour from transfering gasoline drops down below your car and will end up all around your engine bay, a spark could easily occur in this area (from a shorting ignition wire) igniting the fuel vapour and potentially the fuel going into the tank, and the fuel in the tank. Should this happen you will have an extremely bad day.

With the engine switched off there's no electricity going around in your engine bay and so no real chance for sparks. Accidents will always happen, but prevention can reduce the frequency by a huge amount, and that means lives saved or at least not destroyed.

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Bimimans t1_ixtz9lh wrote

Why would you want to keep your engine running anyway?

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1

MajorFrantic t1_ixt40gv wrote

On or off doesn't matter to the car at all during fueling.

The prohibition is to help prevent some human caused fire issues, namely generating static charge (sparks) by getting in and out of the car. You can proactively discharge the static harmlessly by touching the car's metal before you grab the fuel dispenser to remove it.

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scooter3513 t1_ixtjri9 wrote

I’ve heard this before…but I get in and out of the car regardless if whether it’s running, so why does that matter?

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BSC25M t1_ixtx2e5 wrote

Not entirely true…

The gas gauge doesn’t always act properly when the car is on for the fueling…often takes 15-20 minutes of driving to adapt…

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lemon-choly t1_ixtwn9g wrote

I have filled up my tank with the car on before! Multiple times. Not the safest but it can be done just fine

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Adonis0 t1_ixteoum wrote

Well, if you like standing in fumes that will cause toxic long-term cumulative effects sure, there’s no danger.

No need to be exposing yourself to more fumes than needed though

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Acecn t1_ixtki7u wrote

I have to wonder if the added fumes from your idling automobile would make a detectable difference in the air quality of the average gas station environment.

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[deleted] t1_ixt5x3m wrote

[deleted]

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BigChiefS4 t1_ixtlxd7 wrote

Your engine oil will not freeze. WTF are you talking about? I live in MN. In northern MN it regularly gets well below zero. Last winter it was below -40F and my Q5 TDI started right up after sitting outside overnight. If the oil was frozen ( which it won’t), the engine wouldn’t even be able to turn over.

Even if it COULD freeze, it isn’t going to in the 5-10 minutes it takes to fill up your gas tank.

So much misinformation in the thread…

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kyrsjo t1_ixu2h7p wrote

Yeah, a huge lump of iron sitting inside a somewhat isolated bay won't go from pretty warm to -40 in a few minutes. That said, starting a really cold diesel isn't fun, and probably puts a ton of wear on it. Fuel freezing isn't really a problem tough, since there is a different fuel blend in the winter...

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BigChiefS4 t1_ixuq4lj wrote

Yeah, my Q5 TDI was not happy to have to start in -40F temps, but it did start. I let it idle for a good half hour, just to get the fluids going. The thing with diesels in the winter is that they are more efficient engines and don't run as hot as gas engines, so they take forever to warm up.

​

After letting it sit idling for a half hour, I drove the 10 miles into town (we were staying in a primitive cabin in the middle of the woods) and by the time I got into town, my temp gauge had just started to move up. When I pulled into the gas station, it went right back down to zero. On the drive back, it barely moved.

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GingerScourge t1_ixtiv1c wrote

> In super cold conditions (and I mean like -40°) it's actually recommended to not stop the engine while refueling as the engine oil could freeze in that time and the car not be able to start again.

Can confirm. I lived in Fairbanks,AK for a couple years. And when the thermometer dropped below about -10F, I kept the engine running.

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BigChiefS4 t1_ixtm396 wrote

Confirm what, exactly? Engine oil does not freeze. It gets more viscous, but it doesn’t freeze. -10F is not that cold. It’s that cold most of January and February here in MN, and my Q5 TDI starts up every day.

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Willbilly1221 t1_ixtes26 wrote

Dont quote me, second hand knowledge here and i dont know how true it is. I was told that the automatic stop on the trigger from the pump works better when the engine is off. Something about the running engine that dosent happen all the time but can cuase the pump handle to not shut off when the tank is full causing a spill on to the ground. Again my source said it dosent happen all the time, and i cant verify my sources info. Beyond that i dunno.

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nesquikchocolate t1_ixtjw7j wrote

The sign predates automatic stopping refueling nozzles, by many years.

Cars were significantly more dangerous in the early years, with very few regulations helping guide designers around safe refuelling practices.

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veemondumps t1_ixt3qll wrote

Carburetors and older/cheaper fuel injection systems use a mechanical switch to determine how much fuel goes into the engine. This switch is usually controlled by a float that is quite literally floating on some of the gas that is entering the engine. If too much gas is entering the engine, the float rises and pushes the switch closed. When the level of gasoline drops, the float sinks to allow more in.

The buoyancy of that switch is calibrated against the amount of gas that the fuel pump is delivering to the engine - which will be a fixed value. IE, if the fuel pump is delivering 1 psi of fuel to the engine, the float will be set to press on the switch with 1 psi of pressure when the fuel supply needs to be cut off.

Pumping fuel into your car can increase the amount of pressure in the system, which can increase the amount of pressure coming out of the fuel pump - particularly when the tank is near full.

So imagine that your tank filling up causes a pressure surge and that 1 psi of fuel normally coming out of the fuel pump briefly spikes to 5 psi. That's going to mean that the switch in your carburetor/fuel injector doesn't close and more fuel keeps going in even though the engine is full. That could potentially flood your engine.

A flooded engine can be anything from a minor inconvenience to something that burns out your starter motor.

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tiedyemike8 t1_ixt4ruy wrote

There is no way that filling the tank will change the output pressure of the fuel pump. I'm sorry but nothing you described here is accurate.

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mypantsrblue t1_ixtbb3j wrote

Yeah what a long winded rant that came straight from absolutely nothing accurate. Peak Reddit.

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BigChiefS4 t1_ixtlj8a wrote

Not a single word of this is true. Complete made up bullshit.

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DLBaker t1_ixtm8ai wrote

>Pumping fuel into your car can increase the amount of pressure in the system, which can increase the amount of pressure coming out of the fuel pump - particularly when the tank is near full.

Hell to the no it can't. Pressure is *regulated*. Also, I haven't seen a carburated vehicle sold since the '90s. That little needle valve attached to the float will regulate flow more than it will regulate pressure.

~ Signed: Old guy that's rebuilt his fair share of carburators.

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Ez13zie t1_ixt4m6c wrote

Seems like this guy vehicles.

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