Can you leave the engine running the whole long trip? Even to gas up?

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The other thing is with those long trips how are you gunna check the oil? Even non oil burners can consume some on long trips.

Or out of nowhere, you'll spring an oil leak you didn't have prior. Almost ran my truck out of oil on one PA trip. The head gasket just decided to start hemorrhaging oil. Luckily I smelled the oil and shut it off and checked next time I got gas.
 
On a related note: Is it OK to smoke while reading in bed? I do it all the time and if I get really sleepy I just make sure to reach over and put the cigarette out. I haven't had any fires yet.
It's safe unless you want to keep all your toes, and avoid stents or saphenous vein grafts to your coronaries.
 
Your EVAP system does a valve lineup where under certain scenarios it's doing a tank purge, sucking "vapors" from the top of the tank through the intake with the car running. If you fuel it while it's running, you can send liquid fuel down those lines, flooding out the engine or at least making it run bad.

My Prius gets "refuel ready" when I open the gas lid. One time I was in line for gas, preemptively opened the lid, then restarted the engine to pull forward in line. It didn't take fuel! It must do some sort of valve lineup that excludes fuel from the filler neck when it's not "refuel ready." Go figure.
 
New Jersey is the only state where it is illegal to pump your own gas. An attendant will fill up your car just like in the old days. I doubt seriously that the pump jockey is going to allow you to leave the engine running during the fill-up

Oregon for the most part, although I think they modified their rules to allow for self-serve in some lower population counties under certain conditions. I think hiring enough workers was the issue there.
 
Apparently there's a greater chance of static when the engine is running. But then again I see things that aren't recommended (with regards to static generation) such as getting back in a car during refueling and going back and touching the handle.
 
⛽️ Since we are a whole 7 days away from Manteno Illinois... and this thread could be for any car, any time... Can I leave the car running the whole time? Do I have to turn it off to gas up which I will probably have to do about 3 times, top up before leaving NJ because of lower fuel cost to save $$ then again in Ohio if possible and from there should be OK to somewhere in Illinois and that part of journey.. Is there really a need to turn the car off?

I estimate fill-ups take about 5 minutes at a time, usually in Ohio I use the restroom, MAYBE buy a snack, and then gas up the car, putting in about 14-15 gallons takes about a whopping 2 minutes, since most don't know the pump rate is supposed to be 7 gallons a minute. Some aren't but most are. (Some run slower some try to go super fast.)

I don't think I'll set an EVAP code but... Seriously. Is there a need to turn the car off? Or only when at destination . Any car, really..
I'll admit up front to not reading 4 pages worth. Why in the world would you not turn it off? What is the point of leaving it running other than to waste gasoline and waste money and pollute the environment that little bit extra? Really curious what in the world this thought process is.
 
I do it all the time, especially when traveling with the camper. Usually there is a dog in the truck and between the wife and I there's always a person with it. Plus, the little 2.3L Ecoboost is working hard when we're towing, so leaving it running keeps the fluids flowing. We usually gas and go, food and restroom is attached to the truck if needed.
 
SwampSurvivor said:
Or out of nowhere, you'll spring an oil leak you didn't have prior. Almost ran my truck out of oil on one PA trip. The head gasket just decided to start hemorrhaging oil. Luckily I smelled the oil and shut it off and checked next time I got gas.
must be a six point uh oh. :)

except that the 6.0L is a diesel, and he stated he stopped for gas ...
 
Well, ignoring the legality, and the optics of a police officer ignoring both state and federal law while in performance of his duties…

Let me ask the inverse - what cognitive, well reasoned evidence do you have of a running car having the same static electric discharge potential as a car that is shut down?

With all the electronic systems operating, the car is switching significant current on and off. There is an increased chance of both vapor, from some fuel systems that are circulating fuel, or recovering vapor, using electric pumps, and static discharge from increased electric current flow. With all the systems operating, there is an increased chance of static electricity generation…coupled with the increased vapor…and your fire risk goes up.

Though the greatest risk of static discharge is synthetic clothing sliding across cloth seats, not the car itself. That one factor has actually produced static discharge and car fires on occasion.

I suspect the law prohibiting fueling with the engine running comes from the days of poorly shielded ignition systems, and of fuel tanks directly vented to the atmosphere, where increased vapor and more sparks increased the risk.

But since no one has tested the difference between a running car and a shut down car, there is no way to conclusively say they’re of equal safety.

So, with temperatures well below zero, or some other compelling consideration to leave it running, I’ll accept a slight increase in risk for the benefit of leaving the engine running. That is a thoughtful reason to ignore the law on the matter and to accept a change in risk.

We are back to legality once again.
At one point there was also concerns of cellphones somehow inducing sparks that could ignite a fuel vapor fire.

At pumps with vapor recovery nozzles I don’t even note much by the way of vapors anymore.

I never shut a car off when fueling up. I don't do it to be a scofflaw; it's just that I'm often fueling and going immediately right back off the station lot.

I'd be interested to hear a cognitive, well-reasoned explanation as to why it's dangerous to leave the car running during fueling. What is it about a running car that makes it "more dangerous" than a vehicle that is shut off, anyway? A car doesn't become more of a danger in regard to static discharge, does it?

In the rare occasion that I am refueling at a location where I immediately pull off and am at the pump, I will leave it running. That’s fuel stops like on the NJTP, NY Thruway, Ohio/Indiana toll roads etc. But it’s entirely because of heat soak, even if it’s only a sustained ~60kW or so to cruise at typical interstate speeds.




The idea that there is some wear saved on these activities is folly.
 
except that the 6.0L is a diesel, and he stated he stopped for gas ...
yeah, but he's listing a 2001 F350... just thought that would be the mostly likely head gasket blower... on second thought that would have still been a 7.3 though..which weren't notorious for blowing head gaskets.
 
I light up a cigar every time I fill up. Stand by the nozzle. Still do it.

No issues.

That’s makes it OK…I mean, as long as I flick the ashes away from the vapors, there won’t be any problems…because nothing has happened to me, that makes it safe.

🤦‍♂️

What do the stats look like? Open Flame near gas vapors or leaving your car on?
 
One point to bemade about static electricity - creation, and discharge, are two very different things.

While it may be created by the sliding across the seat, the discharge from the operator has happened at the nozzle, where the vapor is present. Just touching a ground between exiting and lifting the nozzle, will safely discharge that static build up.

Cars themselves, are not grounded at all. That is WHY static electricity can build up on a car - they’re insulated by rubber (tires) so they can, and often do, have a static charge. Where does the charge come from? How is it generated?

Look, all of these static discharge/spark scenarios are rare. Question is - who gets to choose the risk?

Would anyone be OK with the Captain of your airliner saying, “I’m going to go for it. It’s probably safe”?

If the law is truly useless, because the safety assessment has been done, then it is time to get rid of it.
Rubber tires contain a large amount of carbon (~22% which is why they are black), and are not insulating the car from ground. The positive charge is generated on you as you slide out of the seat, and discharged to the negatively charged car when you reach for it again.
 
Because this is dangerous. The signs at every gas station should be a clue.
 
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Some old 90s BMW owners might remember discovering that even merely leaving the ignition in the "on" position (engine off) during refueling would cause the instrument cluster to get confused and throw the fuel gauge out of sync and have it return a false (empty/dead) reading. Which required pulling the relevant fuse to reboot it and get the gauge working again.

With saddle/butterfly-style tanks, and dual level senders, displaying an accurate fuel level requires some smarts, but it doesn't account for unexpected beahvior on the part of the drivers.
 
For what’s it’s worth, I have always left my car running during refueling. 20 plus years. I have four cars , so I’m at a gas station about 2-4 times per week. I never let my cars get under half a tank so I’m frequently at a gas station.

The purpose of leaving the car on is to keep the AC running (live in south Florida, it’s HOT) and to put less wear and tear on the starter motor. I figure that over a 5 year period I probably save at least 400-500 starts per car by not turning my car off at the gas station.

I don’t think it’s an inherently dangerous practice, plus, I always ground the car to the fuel nozzle to prevent any sparks before I begin fueling, which is a good practice anyways.
 
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