another consideration is the accumulation of very fine sediment that sinks to the bottom of a fuel tank

Mar 6, 2026 11:15 PM

CitizenK9

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This is overblown advice. Maybe this matters a bit more in the summer or in desert climates, but in normal conditions, it isn’t meaningfully impacting your fuel pump’s service life. All of my cars have easily gone over 200K miles without ever having a fuel pump issue, and I don’t baby their fuel levels. Mathematically I’m in the ballpark of somewhere around 1,300 fill-ups over the last 21 years of driving, and I’m in SoCal, which is considered a harsh environment on vehicles.

1 month ago | Likes 4 Dislikes 0

Corporations, is it bad to design car parts that fail for such a standard fuckign concept?

1 month ago | Likes 2 Dislikes 0

Justin: "Ask my wife. ..."

1 month ago | Likes 4 Dislikes 0

Today I learned....

1 month ago | Likes 2 Dislikes 0

Interesting to come across this. Subaru Forester ran out of gas twice in the last year or so; once w/ the guage indicating a little less than 1/4 tank, next time w/ indication of a little more than 1/4 tank. Turned out to be exactly this problem. Replaced the fuel pump ($1400), no problem since. Sounded like BS when my mechanic told me about it, but sho 'nuf, that was the problem.

1 month ago | Likes 3 Dislikes 0

this isnt true anymore. ive tested it for decades. running very low and even running out dry one time. it doesnt break or destroy anything.

1 month ago | Likes 7 Dislikes 2

Not sure if this is completely true. Fuel pumps are usually located inside a "bucket" that is full of fuel even though your tank is not. Not sure if this applies to all cars but I have seen this many times. The bucket prevents the pump from surging in corners and keeps it cooled.

1 month ago | Likes 2 Dislikes 0

I always just fill my tank halfway when it's on E. I'm currently driving a 12 year old WV Polo that iv'e owned for 6ish years. Never had an issue with the fuel pump or with any other car I've owned.

1 month ago | Likes 3 Dislikes 0

Logical, but how often has anyone had to replace a fuel pump because of this? I've owned dozens of cars and never replaced one.

1 month ago | Likes 12 Dislikes 0

"It's a commonly believed fact!"

1 month ago | Likes 3 Dislikes 0

I bet they're gaslighting us

1 month ago | Likes 19 Dislikes 0

Why is this not the top comment?

1 month ago | Likes 3 Dislikes 0

because people havent upvoted it more

1 month ago | Likes 1 Dislikes 0

Wtf are these guys telling its total bs as long as fuel runs trough the Pump its is cooled and as long as the Pump dont run dry the Pump will not notice any fucking differents in your tank it dont give a fuck if it running on the last liter or if its filled up to the top...

1 month ago | Likes 6 Dislikes 2

It'll cool the actual pump mechanism, but not the motor. The fuel doesn't run through the motor, but the motor does get submerged when the tank is fuller. And it's the motor that gets warm.

1 month ago | Likes 2 Dislikes 2

Every time I fill the tank in the hoopties that I drive, my car shits the bed and I lose $60 in gas, so there's that.

1 month ago | Likes 2 Dislikes 0

That seems like a design flaw. Don't they know us poor folk can't put more than $10 in at a time

1 month ago | Likes 7 Dislikes 1

Cars break so easily.

1 month ago | Likes 2 Dislikes 0

It was a design flaw... On GM cars in the early 90's. It's BS because it's like saying because Nissan Leafs had no thermal management, all EV batteries would degrade quickly, even though that was literally the only EV so badly designed. Or like... because some people are allergic to wheat gluten, wheat gluten is bad for human health to eat.

1 month ago | Likes 2 Dislikes 0

I used to keep it on e a lot, and eventually my car would start, but stall when I'd give it gas. Sediment had clogged the fuel filter. Since then, I try to not let it stay on e, avoid old gas stations that might have rust in their fuel tanks, and try to avoid getting gas when it's been raining, so I'm less likely to get water in the gas

1 month ago | Likes 9 Dislikes 3

Unless the gas station stores the fuel in the open air (which would be horribly inefficient, not to mention illegal) or rain is falling directly into the opening on your gas tank, no rainwater is getting in your gas tank

1 month ago | Likes 2 Dislikes 0

https://www.wsiltv.com/news/contaminated-fuel-at-local-gas-station-to-blame-for-multiple-vehicle-breakdowns/article_9b656aee-4e74-4f">l">https://www.wsiltv.com/news/contaminated-fuel-at-local-gas-station-to-blame-for-multiple-vehicle-breakdowns/article_9b656aee-4e74-4f11-bf7b-6cbd713e0d03.html

https://www.13wmaz.com/article/news/local/state-confirms-water-in-gasoline-at-macon-gas-station/93-a10e91b0-2dd9-4752-b51e-b37bfe354243

1 month ago | Likes 1 Dislikes 0

The rain thing is fallacy, that's not how fuel tank storage work.

1 month ago | Likes 8 Dislikes 1

I must have gotten the wrong idea from the news stories from people getting water in the gas after heavy rains and having to have their fuel drained out around here

1 month ago | Likes 1 Dislikes 3

Now condensation is another story. But there are sensors and temp gauges that see all that. It's done before every fuel drop. Has to meet parameters or they get no drop

1 month ago | Likes 1 Dislikes 0

It's a fallacy in that it shouldn't happen, if it does, it means the tanks aren't being maintained & those fuckers need to be fined for it.

1 month ago | Likes 3 Dislikes 0

side note, ancient or "classic"... cars tend to have a bunch of random rust n shit sloshing around in there, it's best to keep that a diluted as possible, soo, same basic rule like 1/2 a tank all the time.

1 month ago | Likes 107 Dislikes 4

The first thing I thought, man I'm old... I doubt the modern tanks are metal so at least rust shouldn't be a problem.

1 month ago | Likes 2 Dislikes 0

Thats more a old wives tail.
Fuel is sucked from the bottom of the tank. Any trash will get sucked up if the tank is full or very low.
Fuel pumps have a "sock" on them so the fuel goes through that and keeps any large pieces from getting into the fuel pump.

Letting it get low, on older vehicles, can be an issue as they did not have the same baffles as newer tanks so low fuel and a hard corner and you can suck up air.

1 month ago | Likes 7 Dislikes 0

My first car (77) had an extra filter in the fuel line easily accessible. Whenever the car died, reach under the hood, disconnect and blow it out, reconnect. Good for another 250mi or so.

1 month ago | Likes 24 Dislikes 0

It would help, also, if you turned your key while you had the filter removed, making the starter try and start your car and causing the fuel pump to pump gas. The built up sludge and debris in your fuel line would be pumped out, clearing your fuel line.

1 month ago | Likes 18 Dislikes 0

Anyone driving an ancient car should have the fuel tank, pump, filter, injectors, and all soft lines replaced at this point. It will leave you stranded.

1 month ago | Likes 3 Dislikes 0

true, and also a giant pain in the ass, soo...

1 month ago | Likes 2 Dislikes 0

This is bullshit, because as long as the fuel pump is able to pick up fuel, it has cool fuel INSIDE it, which cools it as it operates

1 month ago | Likes 28 Dislikes 4

It depends if the pump is in the tank or outside. Yes both exist

1 month ago | Likes 6 Dislikes 2

Which type of fuel pump doesn't have fuel inside it?

1 month ago | Likes 2 Dislikes 1

I'm pretty sure it doesn't matter. Both have fuel running through them.

1 month ago | Likes 6 Dislikes 1

It wouldnt cool the motor powering the impeller

1 month ago | Likes 3 Dislikes 3

I did have this happen to me in a 01 Chevy Silverado. I was on empty and when I stepped on the gas, I could hear something falling apart and it lurched forward amd stopped in the intersection

1 month ago | Likes 2 Dislikes 0

I drive a tiny car. Gas is so expensive that im always at a quarter after 20 dollars.

1 month ago | Likes 4 Dislikes 1

If you go up hill and not even quite E the fuel sloshes away from the fuel pump and you die.

1 month ago | Likes 2 Dislikes 0

I'm pretty sure this is ancient advice from the early days of fuel injection. On any car I've seen the pump on recently, the pump is way up top and would be out of the fuel by the time you're down to 3/4 tank.

1 month ago | Likes 2 Dislikes 0

(laughs in EV) so many silly unnecessary parts 🤦

1 month ago | Likes 2 Dislikes 0

We sidestepped all that nonsense 👍😅

1 month ago | Likes 2 Dislikes 0

I have a hybrid vehicle, so I’m at least partially protected. Half the time I’m rolling on battery power.
Having said that, I still keep my tank half full at a minimum, and fill up more often.
As a side benefit, when the time comes to run from the impending apocalypse, I’ll at least get a few hundred miles away.
(Just kidding, sort of.)

1 month ago | Likes 5 Dislikes 2

Just don't drive with a _flashing_ "check engine" light. That's deadly.

1 month ago | Likes 4 Dislikes 1

Depends, on my last car 'check engine' was a generic light for any fault, including stuff not strictly about making the car go such as the side impact sensors. I think that just disarmed the airbags and that was it, the real pain was that to be sure about diagnosing it and fixing would require the manufacturer tool to plug into the OBDII even before thinking about replacing anything

1 month ago | Likes 2 Dislikes 3

Normal CEL is emissions/engine efficiency stuff (O2 sensors, misfires, A/F imbalances, ignition timing problems, etc) Flashing CEL is your engine telling you it is moments away from catastrophic failure

1 month ago | Likes 3 Dislikes 0

Some DTCs can be indicative of actual big engine problems - like if you're getting an excessive knock code you should for sure check that out, but really most of them you can drive along just fine with the biggest issue being if you're in a state with emissions inspections. Flashing CEL is always a very very bad thing to see

1 month ago | Likes 3 Dislikes 0

I drove it long enough that the light went off so the engine fixed itself right? 👍

1 month ago | Likes 7 Dislikes 0

As someone who's taken my fuel pump out more times than I can count I can assure you that its no longer submerged way before 1/4 tank. Every cars tank design is a bit different though. Not the end of the world. No sediment eother, My cars over 10 years old and there is zero shit at the bottom of the tank even with me dickin around in there so often

1 month ago | Likes 2 Dislikes 0

Either*

1 month ago | Likes 1 Dislikes 0

Not all fuel pumps are in the tank. Most are, but not all.

1 month ago | Likes 2 Dislikes 0

Likely good advice. But my experience and priorities differ. For example, my entire driving career has been cars with 200k to 300k miles. I’ve lost head gaskets, timing belts, radiators, clutches, alternators…. Never lost a fuel pump…

1 month ago | Likes 70 Dislikes 4

Same

1 month ago | Likes 4 Dislikes 0

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1 month ago (deleted Mar 7, 2026 4:53 PM) | Likes 0 Dislikes 0

Might be your reaction time.

All those people may be at fault... But perhaps you could have avoided it. 4x times makes me think you are slow to react.

1 month ago | Likes 4 Dislikes 1

I've never had a car past 250,000, but I once hit an elk, and four times people turned left in front of me.
Each time their insurance paid out.
I've only had one car wear out.
I've never replaced a fuel pump.
I've replaced all of those components, though.

1 month ago | Likes 2 Dislikes 0

They never go out if you never fill up. The harder they are to get to, the longer they will run on E and faster they die on F. It's true.

1 month ago | Likes 5 Dislikes 3

Then you never owned a tahoe.....lol

1 month ago | Likes 7 Dislikes 0

First I've ever heard about this.

1 month ago | Likes 188 Dislikes 1

Likewise, but I've also, I was always told not to let it pull the dregs through with sediment in it.

1 month ago | Likes 1 Dislikes 0

Not that big an issue since most fuel tanks have been plastic since the late 80’s. Before then, steel tanks caused condensation and resulted in rust-flakes damaging/jamming the fuel pump.

1 month ago | Likes 2 Dislikes 0

Same. They even had a question about it on Car Talk a few years back. The question was framed from a couple whose husband always liked to drive around low on gas because it meant the car was lighter and got better mileage. Their answer was that it barely made any difference. They did not bring up the fuel pump.

1 month ago | Likes 12 Dislikes 0

I used to regularly drive on almost empty because I'm lazy and didn't want to take the time to stop. Once I had to get my fuel pump replaced I stopped that.

1 month ago | Likes 4 Dislikes 0

How many miles until it failed?

1 month ago | Likes 1 Dislikes 0

I made it all the way to the tow truck.

1 month ago | Likes 1 Dislikes 0

it's only been a thing since the advent of electronic fuel injection, previous to that -- fuel lines were low pressure ~10 psi. now they are ~90psi.
so only the last 30-40 years.

1 month ago | Likes 63 Dislikes 0

So pretty much valid for most drivers outside of Cuba.

1 month ago | Likes 9 Dislikes 0

Even older and the mechanical pumps were only a few psi, and run off a cam on the engine.

1 month ago | Likes 16 Dislikes 0

Because it is bs

1 month ago | Likes 10 Dislikes 10

Don't know why you're getting down voted. It is. Electric fuel pumps also come in external, and flow a lot more than your factory fuel pump which should imply more temperature... so maybe the fuel flowing through it is enough after all and this all just bullshit.

1 month ago | Likes 4 Dislikes 0

Yeah, letting it run empty, or nearly empty, sure.
Not driving when its 1/4? Bullshit. Maybe within one gallon minimum, but why would someone design a vehicle where you can only use 3/4 of the tank?

1 month ago | Likes 2 Dislikes 0

First I've heard about this was back in 1995.

1 month ago | Likes 1 Dislikes 0

It's not a part that dies too often, unless you constantly drive like this, but also I find a lot of cars fudge the numbers a little bit, so when it says 1/4 left, there's usually a bit more than this, partly to protect the pump, and partly to save people from their idiot selves and getting stranded :)

1 month ago | Likes 39 Dislikes 0

My old Corolla was like this. Needle hitting empty meant there was ~1 gallon left.

1 month ago | Likes 10 Dislikes 0

Not saying it was the smartest decision I ever made but I made it 45 miles with the DTE showing less than 10 miles remaining (it literally stopped going down once it hit 10, if you're that dumb, godspeed) and this was a loaded semi (so you see why I couldn't just go to the next gas station). Fukin made it. Needed a new fuel filter for the trouble, but I made it. My usual planned fuel stop ran out of the go-go juice and I coasted that big girl into the next option on fumes and prayers.

1 month ago | Likes 4 Dislikes 0

driving a prius that can just switch to battery for driving at any time has made me VERY cocky sometimes. My economy record for an individual drive was 72.6 miles to the gallon, with 1/16 tank left

1 month ago | Likes 7 Dislikes 0

Wow

1 month ago | Likes 1 Dislikes 0

I once drove 4 miles on "0 Miles to E". I stopped for gas off an exit in BFE, station was all lit up (including an open sign) and I swiped my card, it processed and said to start pumping, but it didn't pump any fuel. I tried another pump, same thing. I went to go inside and the door was locked. Attendant yelled from inside "WE'RE CLOSED". I'm like, WTF mate? A pay at the pump gas station that closes?

1 month ago | Likes 2 Dislikes 0

Luckily I did have enough gas to reach the next exit on the highway, but it was a little bit of a nail bitter.

1 month ago | Likes 2 Dislikes 0

I've done similar in my old civic when all the fuel bars are gone and the orange "you're an idiot" light was on. I definitely understand the nail-biting feeling. Though once I got to the station I could only put 45L into a 50L tank, so I think they keep 10% on reserve for idiots like me :)

1 month ago | Likes 1 Dislikes 0

Yea, I put 19.2 gallons into a "19 gallon" tank....

1 month ago | Likes 1 Dislikes 0

As a person who has some experience in the automotive repair field, or at least with a certain product line, this isn't a problem. I've heard this theory many times over, but just not seeing any pattern to prove it. Now things may be different with vehicles outside my area of expertise. Regards.

1 month ago | Likes 29 Dislikes 1

It was more an issue on older cars. Newer ones have baffles that keep the fuel around the fuel pump. So going around corners, even low, does not cause the same issues older ones did.

1 month ago | Likes 1 Dislikes 0

I agree with you. Logic tell that the fuel going through the pump will cool it too. Running a pump dry is really bad tho.

1 month ago | Likes 10 Dislikes 0

Yeah this, the fuel in the tank isn't doing shit to cool the pump, there is no thermal path from the pump to the fuel in the tank.

1 month ago | Likes 3 Dislikes 0

From my understanding, tank/pump designs have improved quite a bit to prevent this. 80s/90s it was definitely an issue. But still, not bad advice to follow in general, not all brands/models may be doing the same thing.

1 month ago | Likes 6 Dislikes 0

"It's a commonly believed fact!" I remember twice going to a shop to get my Honda Insight (2000) oil changed. And TWICE having to have it changed a second time because they put 5w fucking 30 in it and the engines in those cars were the first in the US calling for 0w20 so they were the first to each high mileage. Both times at two separate places they said "it's got 150k on it, 0w20 is too thin." The second time was the last time anyone but me ever changed the oil in any of our cars.

1 month ago | Likes 2 Dislikes 0

The insight forum had a spreadsheet of cars with high mileage and there were something like 14 of them with 400k+ miles and one with 720k miles on it (totaled when they hit a deer on the interstate, sadly). Never used oil. Sold it with 230k on the clock, sounded like a sewing machine at idle (solid lifters). Miss that car... I contacted the guy I sold it to recently, it's got over 300k on it now.

1 month ago | Likes 1 Dislikes 0

So …. You’re saying it’ll be fine?

1 month ago | Likes 36 Dislikes 1

Sure

1 month ago | Likes 3 Dislikes 0

Some cars you can quickly access and remove the fuel pump assembly, swap in a relatively inexpensive motor, and you're back in business. Some cars require dropping the exhaust, rear axle, and removing the fuel tank (had to do this on a Camaro recently) and, well, no one wants to do that. It's 100% a smart idea to always keep at least 1/4th a tank of fuel in a car to keep that pump alive.

1 month ago | Likes 12 Dislikes 0

Oh yeah and some cars, the only way to replace the fuel pump is to buy the entire assembly, which can range from $100-$800 just for the part, plus the labor to install it. Good times.

1 month ago | Likes 1 Dislikes 0

And when the pump stops, don't manual run it a few times to "top off" else you risk filling your charcoal canister with liquid fuel, which will set a check engine light that'll fail emissions, and can cause hundreds or more to replace. When the pump stops, just stop fueling. It's worth it.

1 month ago | Likes 8 Dislikes 0

A friend of mine was a GM engineer and one of his early assignments was driving around in an astro van, only adding 1 gallon of gas after it ran out, repeatedly, to test this situation.

1 month ago | Likes 10 Dislikes 1

Yeah sorry, that friend is pulling your leg. Nobody is going to pay an engineer to drive around like that. That's not how you test these things.

1 month ago | Likes 2 Dislikes 1

He told me about this when we were both ~22 years old and he was thinking starting work for GM might have been a mistake. Would be a weird lie. Anyway, he's still there and he's on the Cadillac LMP car team. Even said a few words in one of the promo videos.

1 month ago | Likes 1 Dislikes 0

There are much easier ways to test this

1 month ago | Likes 3 Dislikes 0

At the end of the day, real world testing can't be replaced. accelerated life testing is great and super important, but it's not the end-all be-all

1 month ago | Likes 2 Dislikes 0

Makes sense

1 month ago | Likes 2 Dislikes 0

They all have the same story. It's obviously a conspiracy! (/s)

1 month ago | Likes 339 Dislikes 2

Talk about gaslighting!

1 month ago | Likes 31 Dislikes 0

You can tell they were coached ahead of time.

1 month ago | Likes 10 Dislikes 0

These guys say this, but I’ve also heard that it takes as long to charge your battery from 80% to full as it does to go from empty to 80% at a DC Fast Charger. Who do I believe?

1 month ago | Likes 2 Dislikes 0

Both of those statements seem plausible.

1 month ago | Likes 3 Dislikes 0

1 month ago | Likes 8 Dislikes 0

I love a good charge curve. I canceled an order of a Subaru Solterra and bought a Kia EV6 because of the DC fast charging rates.

My car is a BEAST. Gets to 240kW and holds it to over 50%. Then ramps to 192kW for a while. It’s still over 150kW approaching 75%.

The car has always been ready to leave before I’m done.

1 month ago | Likes 1 Dislikes 0

I didn my own research and according to magafuelpumpconspiracies.com you should drive till the tank is completely dry and THEN fill it up.

1 month ago | Likes 52 Dislikes 1

To make sure it's completely dry, chuck a hot coal from a nearby grill into the tank, the heat will evaporate the remaining gas.

(Don't do that unless you like your car being on fire.)

1 month ago | Likes 2 Dislikes 0

And make sure someone is there to film it so the proof can be put on youtube

1 month ago | Likes 2 Dislikes 0

Oh i get it, just like my phones battery!

1 month ago | Likes 5 Dislikes 0

Works best if it's a diesel!! /s

1 month ago | Likes 27 Dislikes 0

I only use diesel if it's cheaper

1 month ago | Likes 10 Dislikes 0

Up until about 20 years ago, diesel was 1/4 of what regular gas cost.

1 month ago | Likes 8 Dislikes 1

Because diesel fuel wasn’t subject to the same environmental regulations that gasoline was. Now it is.

1 month ago | Likes 4 Dislikes 0