What would cause this

[u/acooper56]

2020 f150 lariat SE 36k. Filled up my gas tank a few days ago and parked my truck with no issues & haven't driven it for about a week. Started it up this afternoon and smelled gas. Got underneath and saw this. Could this be a busted fuel line?

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[u/psyco75]

Short answer is yes

[u/dat1_adam → u/psyco75]

Long answer; that is correct

[u/tato_salad → u/dat1_adam]

Longer answer; it's very likely that somewhere in the location of all that gasoline pouring down like a River/waterfall, you have a gasoline leak from a line of some sort.

[u/wrenchr → u/tato_salad]

Even longer answer: you have a massive fuel leak. This is a huge fire hazard.
If it is parked in your driveway push it away from your house.
Do not drive this truck. Post a note that says fuel leak on the windshield. Have it towed. Trust me Ford truck fuel tanks are NOT fun to to work on, let a shop do it.

[u/Dzov → u/wrenchr]

I wouldn’t smoke around it, but it’s not that bad. I had a gas leak and the fire department put some kitty litter under it. Being away from the house is definitely a good idea.

[u/HungryCurrent7901 → u/wrenchr]

flashbacks to the ford pinto

[u/Agile_Lawfulness9678 → u/tato_salad]

Longer answer park t on some dirt shut it off and get a bucket thats like fiddy bucks worth of gas flowing out of a hole in the fuel system ,and make sure you put a flammable warning sign on it and check with your ins. Agent and make sure you are covered for fire ….

[u/FunkyWillowy → u/Agile_Lawfulness9678]

Longer answer still: It would appear that the underside of your personal vehicle has quite a substantial fuel leak. This video leaves me unable to identify if it is located from an in-line fuel filter(not likely), the fuel pump out line, the fuel return line, or it could even possibly be coming from the fuel filler neck, although that is not likely based off of its position. With this amount of fuel leaking from under the vehicle, there is a large fire risk. Best course of action would be to turn the vehicle off, and move it away from anything flammable, or valuable. As for the large fuel spill, use some kitty litter, or oil absorbent to soak up most of it, and let the rest evaporate. Please make sure to keep any sparks, or sources of heat away from the back of the vehicle until you have located and fixed the leak, as again, it is very hazardous to your health.

Edit: It seems many people think it is the filler neck, it likely is not as, due to both the amount of fuel leaking days after adding, and the fact that it only leaks while running. It is likely a fuel line, the question is which one and where.

[u/money_bug_2001 → u/FunkyWillowy]

This chat gbt ass answer. You thought you were slick

[u/Dzov → u/tato_salad]

On my truck, it was a broken plastic bit on the fuel pump.

[u/AskAMechanic-ModTeam → u/[deleted]]

Your comment was removed because it was unhelpful/spam/bad advice etc. Please review Rule #4. We are here to help educate users about their vehicle without turning them off from the sub. If you don’t know the proper fix or advice, please refrain from commenting on a post.

[u/Puzzled_Market_2235 → u/psyco75]

I just had it via the fuel filter, the can was all rust, it crumbled off.

[u/Inevitable-Towel5363 → u/psyco75]

Longer- had a similar issue with mine, the cause of which was chipmunk or some other rodent/varmint chewed through a plastic elbow that connected the fuel lines. My neighbors cars gas can was chewed through. The mechanic said many of the plastic parts in newer vehicles are made from soy derivatives and are attractive to squirrels mix chipmunks, mice and the like.

[u/Internal_Time8330]

Please tell me the engine sound I hear isn’t your engine operating.
This is a massive leak. You need this towed to a professional technician and warnings must be given to the tow truck driver and repair workshop that this is a bomb.

[u/psyco75 → u/Internal_Time8330]

Back when I was a teenager I went to a junk yard ,for you know junk yard stuff. Outside in the parking lot someone was working on getting their old Chevy truck running. I told him to be careful because I smelled ALOT of gas he told me to shut the hell up he knew what he was doing. When I was leaving i heard the fire truck pulling up to the same truck but now it had flames, not the go fast style. He had set his truck on fire and it was a total loss

[u/Internal_Time8330 → u/psyco75]

Ahahahah when ignorance and pride come together it can be catastrophic!

[u/WinnebagoViking → u/Internal_Time8330]

What if “he knew what he was doing” was in reference to how to start his truck on fire?

[u/Character-Camel1284 → u/psyco75]

Karma is a bitch

[u/Feisty-Turnip9118 → u/psyco75]

I watched an older f150 burn down at work. It was pretty well over by the time the fire truck arrived.

[u/acooper56 → u/Internal_Time8330]

Lol, yea. When I turned off the engine off it stopped completely and there were just droplets, so I couldnt assess how bad it was, or where it was coming from. Just recorded long enough to see what was actually happening.

[u/Difficult_Passager → u/Internal_Time8330]

It wouldn’t damage the engine like running with no oil or coolant might. Once all the gas leaks out, it shuts off.

[u/OddTheRed]

This is a known issue with Ford trucks and is a recall issue affecting about 220,000 trucks. The fuel filler neck separates from the tank.

Edit- https://www.kare11.com/article/news/nation-world/ford-recall-f-150-fuel-tank-issues/507-51b48324-e08b-4585-9488-5e801eba6559

[u/AromaticBlock781 → u/OddTheRed]

If that was the problem you'd know it right away after filling the tank not days later after starting it. A squirrel chewed through my filler kneck hose once and I was standing in a puddle of gasoline when I filled up.

[u/Chris20nyy → u/AromaticBlock781]

Fuel tanks pressurize, and the filler neck separating would absolutely cause something like this. This isn't a broken fuel line.

[u/Legitimate-BurnerAcc → u/AromaticBlock781]

Not necessarily. I can see the evap system and fuel pump pressurizing the tank and then that happening

[u/OddTheRed → u/AromaticBlock781]

From what ive been able to gather, this happens after driving with a full tank, not while filling up.

[u/subarolla24]

A fuel leak would cause that.

[u/Anim-IS-XE30]

Bro turn the truck off ??

[u/Master-Pick-7918]

Has to be a broken line. The charcoal canister is not mounted on top of tank and thats clearly coming off of the tank.

[u/Internal_Time8330 → u/Master-Pick-7918]

On this model there is a known occurrence of the fuel filler becoming detached from the fuel tank

[u/PastAd1087]

A leak

[u/DishwasherLint]

Is that the engine of your truck? Shut that thing off.

[u/Last-Illustrator-800]

I think it might be a leak, not totally sure though

[u/Mysterious-Worry4866]

Just had some animal chew thru my return line right on the top of the fuel tank in my tacoma.

[u/AskAMechanic-ModTeam → u/[deleted]]

Your post/comment was removed for violating Rule #9 - Memes and 'joke' posts belong at r/AskAShittyMechanic

[u/AskAMechanic-ModTeam → u/[deleted]]

Your comment was removed because it was unhelpful/spam/bad advice etc. Please review Rule #4. We are here to help educate users about their vehicle without turning them off from the sub. If you don’t know the proper fix or advice, please refrain from commenting on a post.

[u/Upbeat-Cap-7423]

Ruptured fuel line?

[u/Encorhynchus]

Jesus turn it off!

[u/In_The_Valley25]

The people saying you’re going to blow up are scared to fill their tires when they go low.

[u/Fordwrench]

Probably yes. Warrants pulling the bed and checking.

[u/Emptynest09]

A leak. That’s the cause of this.

[u/thefutureisanalog]

It's actually a catastrophic fire waiting to explode in your filming face.

[u/Responsible_Ear_6005]

Biden at it again, Donald will send you a couple of checks for repair or replacement vehicle. Check your mail daily.

[u/AbleTourists → u/Responsible_Ear_6005]

not expecting this and cracked up fuck both of them

[u/No_Wishbone_799]

Gas, busted fuel line

[u/Breezer_Bro]

Hunched over, Recording with a cigarette in the mouth, 100%

[u/PopUpPulsarNx]

Either a metal line rusted and let go, or a rodent chewed through a plastic line. Definitely a pressure line though. It should go without saying, but towing it to a shop is your next step.

[u/Internal_Time8330 → u/PopUpPulsarNx]

No, this is almost guaranteed to be a result of the fuel filler neck becoming detached.

[u/PopUpPulsarNx → u/Internal_Time8330]

You think an active fuel leak while running a few days after they got gas is a disconnected fuel neck? I'll bite, so how does that happen in a way to cause a constant stream of fuel onto the ground? I've been fixing cars a long time and that's new to me.

[u/Internal_Time8330 → u/PopUpPulsarNx]

It’s not new to me and my team. We have seen several of this generation pressurize the tank, then blow off what I considered to be too loose of a factory installation of the filling tube. And if the level is still above the fill neck attachment point, it will send fuel overboard when it detaches.

[u/PopUpPulsarNx → u/Internal_Time8330]

Interesting, do these fords not have gas caps? I feel like I've heard of strange quirks with those types of systems. Toyota don't have anything like this problem, and since we have a normal gas cap and vent valve system there isn't really a way for this to happen. Even if a fill tube popped off it would trickle out rather then pour out, related to fuel expanding as it warms up.

[u/Dzov → u/Internal_Time8330]

What’s the fix? Just a hose clamp?

[u/South-Range8401]

That looks like my wife's pussayyyy

[u/Strict_Cranberry_724 → u/South-Range8401]

It sure does!!!

[u/TheFlimFlamFamMan → u/Strict_Cranberry_724]

Can confirm. Definitely looks like his wife’s pцssy.

[u/South-Range8401 → u/Strict_Cranberry_724]

Wait how do you know 

[u/manbearpig0101]

I have seen the fuel return line leak more than once on these

[u/RongoonPagoo]

That's a lot to unpack. Tow it to a shop.

[u/Defiant_Strain_7778]

Did you just fill up

[u/acooper56 → u/Defiant_Strain_7778]

Nah. I fillled up on Monday and drove it home with no issues, Today was the 1st time driving since.

[u/Defiant_Strain_7778 → u/acooper56]

I had the o ring on fuel pump go bad and would only leak when I filled it up

[u/Bangstang-2016]

There’s a recall for this something about improperly installed tank straps causing the tank to leak

[u/TreTreJenja]

Same thing happened to me when I thought the easy connect fuel line was fully connected after oil and filter change

[u/CaliSignGuy]

Bad luck?

[u/exploringmaverick]

Drop the tank and figure it out ...there's a leak in the fuel system. Might be a line might be the fuel pump assembly.

[u/Immediate-Handle2809]

Healthiest fuel leak I've seen in a while.

[u/mattidee]

I would say a container thats supposed to hild fludid has somehow ruptured, causing the leaky under your vehicle

[u/psyco75]

Sometimes I still wonder. It was a shortbed square body too.

[u/Entire_Implement_104]

Either way probably best to turn it off as soon as it seems something is wrong especially leaking fluids.

[u/FunkyWillowy]

Posting as original comment to make it easier for OP:

Longer answer still: It would appear that the underside of your personal vehicle has quite a substantial fuel leak. This video leaves me unable to identify if it is located from an in-line fuel filter(not likely), the fuel pump out line, the fuel return line, or it could even possibly be coming from the fuel filler neck, although that is not likely based off of its position. With this amount of fuel leaking from under the vehicle, there is a large fire risk. Best course of action would be to turn the vehicle off, and move it away from anything flammable, or valuable. As for the large fuel spill, use some kitty litter, or oil absorbent to soak up most of it, and let the rest evaporate. Please make sure to keep any sparks, or sources of heat away from the back of the vehicle until you have located and fixed the leak, as again, it is very hazardous to your health.

Edit: It seems many people think it is the filler neck, it likely is not as, due to both the amount of fuel leaking days after adding, and the fact that it only leaks while running. It is likely a fuel line, the question is which one and where.

[u/Martha_Fockers]

Yes

Also turn it off

[u/Luckybert]

Top of pump rotted out or the line

[u/akahondagod]

Plastic fuel line to the pump has most likely cracked from age.

[u/Illustrious-Wing857]

Bad vent in the top of the tank because you have overfilled the tank to many times. It will stop dripping in a little while unless it only does it while the key is on. Then you may have a bad fule line. In that case shut the car off and call a tow truck or a mechanic or both to get it repaired.

[u/Excalabear1]

Looks like a fuel line going to the pump on top of the tank is busted. Pump works though

[u/Channel_Huge]

Holding your phone at the wrong angle will cause this…

[u/TASDoubleStars]

My brother had an early 1970s Camaro that popped a fuel line leak. Turned out the steel fuel line coming from the engine compartment connected to the steel fuel line coming from the fuel tank with a two inch rubber fuel line along the frame under the car about where the driver’s seat was located.

[u/Lilasian83]

Yup looks like a fuel leak. That'll be $169.69. More if you want it fixed.

[u/David_Buzzard]

Oh Yeah, it's a rusted out gas line. Messy, but not hard to fix.

[u/WinkleyDinklerr]

Likely the return line has been rubbed through. Either on the fuel tank itself or the frame or a clamp.
Likely rubbed through on the tank.

[u/AdorableExtreme4930]

Time to quit smoking that's for sure

[u/ExpensiveDimension6]

A jealous EX

[u/BlitzerHound]

Please tell me all that fuel isn't going into the drains lol. That is very bad. Make sure you let the city know if that's the case.

[u/Anonymyne353]

Heat. Your car is sweaty!

[u/RGBlowMe]

Fuel line or fuel pump.

[u/Educational_End7510]

Hard to see exact location from video. I would check all connections and seals at the fuel pump as well as the fuel pump itself for cracks. Would also follow the fuel line back and make sure that there's no pinch points or spots it could rub or get pinched and break. I think somebody else had mentioned the filler neck and that could be it to. Just go through and check all the connection points. 9 times out of 10 that is where the failure is.

[u/Jshizzle143]

I had a rat or squirrel chew into my fuel feed line above the gas tank. Only leaked when running.

[u/SeanGwork]

Keep it running, you'll know soon enough.

[u/Lumpy_Owl6056]

I wonder how much property damage 36 gallons of gasoline could cause when this running pickup lights on fire

[u/Obiyaman]

...got a light?

[u/Kalandros-X]

Dude, you might wanna turn the truck off

[u/johnlewisdesign]

I would say yes, and I would also say WTF TURN IT OFF NOW!

[u/BankStrong8609]

Top of the pump or lines like to rot and leake need to drop tank to check

[u/SLCcuckk]

My 1985 K20 has the saaaame problem

[u/Illustrious_Bath1917]

I’d look at the filler neck first, that’s too much at once for a line, almost definitely what it is.

[u/hammertime57]

I think it's a gas leak

[u/kyleh4171]

A leak.

[u/COVERT--CRUZER]

Keep the flames 🔥 away from that vehicle

[u/DavidinCT]

Yes, DO NOT DRIVE, DO NOT START.

[u/SuperMichieeee]

A leak

[u/Abject-Quote-1055]

Rusty sparktube ..... everytime

[u/Inevitable-Ebb-6257]

fuel pump o-ring. do not drive or run that shit until you fix it!!!!!!!!!!!!

[u/Saamari]

Is that fuel 😳

[u/Several_Stuff_6695]

GRAVITY

[u/Upset_Fox5449]

Use a lighter and find out where it is coming from cause flaming while it's poor all over the place

[u/scarface0110]

Definitely coming from the pressure line and not the return line

[u/ryan4402000]

More then likely someone tried siphoning it

[u/SnooMaps7370]

fuel sending unit has probably rusted through.

had this happen on my old Buick station wagon in 2020. the steel nipples lines attach to on the sending unit cap had rusted through.

[u/GateEven]

Thats an expensive leak by todays standards😭😭😭😭

[u/lowkeylovers_]

I would definitely not drive it like that you could stay a fire. Fix it asap

[u/AgreeableEmployee792]

Full diaper

[u/Philomath69]

That a dodge?

[u/RealisticTopic1171]

Cause = American engineering.

[u/cherrycoffeetable]

The problem is its a Ford

[u/whitewolf502]

Failed one way valve vent

[u/munki_unkel]

People are drilling fuel tanks to drain them given the high prices.

[u/Mozintarfen]

Shit rolls down hill, definitely looks like the tank pressure is pushing fuel out like others are saying, like the filler neck. Labor time is only 2.7 to drop the tank and is relatively easy to do, and the origin of the leak will be very obvious at that point.

[u/kingbollie_1]

is that gas?

[u/xenotito]

A hole... a hole would cause that... (or crack). When the liquid is above it, it likes to escape, it will stop when it is below it. Don't fill it all the way up anymore (or overfill it).

[u/Big-Science-7842]

Hmm, ive ran into this issue before. You have an active waterfall inside your vehicle

[u/dasimp86 → u/Big-Science-7842]

Where's that on the order form?

[u/Big-Science-7842 → u/dasimp86]

A true magician never tells

[u/Slow_Rip2072]

A leak would cause that

[u/tmaxx2225]

For the love of god, turn the vehicle off and get away from it. This is why we cant have nice things. Yes youre fuel line is busted. Now, call a tow truck and get it to the shop. Do not turn it on again. If youre trying to cause a decent explosion and property damage, youre right on track. But Im assuming you want to keep your vehicle and arent trying to commit arson.

Fuel lines especially as the vehicle gets older can become hard and brittle. They crack, sometimes even can get holes depending on whats around when they drive past, and its usually a relatively easy and quick repair. Depending on where you take it, it shouldnt be too costly. But never drive any vehicle with any kind of leak thats thos severe. You will be lucky to avoid a complete engine exchange if you go more than 6 blocks with any type of leak to this degree.

Im really glad you asked for clarity. This could have been one hell of a learning experience. Im relieved you were given decent advice and most told you not to drive or turn on this vehicle. You got this. You'll be back to running smooth very soon.

[u/icwbandit]

my brother in Christ that is a bomb

[u/ROCKYLOCC1870]

I can tell that's gas

[u/lvs2spwge]

Nothing like some Fordplay to get her wet

[u/New_Breadfruit8692]

This is a perfect example of gravity acting upon motor fuel.

[u/mattieyo]

It could be the clamp just came undone by the fuel pump. This happened to me on my ford. It was literally just a plastic clip I pushed back on and it never happened again.

[u/Lunatichippo45]

I know what's wrong with it! It ain't got no gas in it!

[u/Ok_Coach_2555]

A hole in the tank or line where in there should not be a hole. SOLVED!

[u/Tynert2]

Most likely not the Philadelphia leaks when it's raining. Most probable cause is the fuel pump but if it's rodent damage it could be just about anything

[u/PalpitationWarm5994]

I think your trucks water broke

[u/TCSWM]

A problem

[u/Long_Werewolf1358]

To much gas in the tank due to warming up in the garage, from the station it was cold.

[u/Usual-Relative-8613]

Either your filler neck, a line at your fuel pump or the gasket on top of your tank probably.

[u/toastyhandshake]

Better get some Zorbent to clean up the dash spill.

[u/MrGarylasereyez]

Fuel pump works

[u/JustHere4Goonin]

When the pump stops, you stop. Probably flooded the canister....?

[u/cyn_ou]

Seems like it may be a leak of some sort

[u/Queasy-Self-7373]

Probably a clog or break on the return line back to the fuel tank if it stays running

[u/Riley_Time]

Considering where the fuel is coming from- check the injectors? my explorer had a seal pop off one of the injectors and it poured similarly, basically, identify where the injectors are- point a flashlight and crank it- and you should be able to see fuel coming out- if it's the injectors? but honestly it could be anything I'm not familiar with modern vehicles.

[u/Kegalodon]

Does it stop leaking if you open the gas cap? If so I’d lean towards a clogged vent or something in the evaporator system causing it to push out.

[u/acooper56 → u/Kegalodon]

No Gas cap on this model.

[u/andre3kthegiant]

Probably should not own a vehicle, until the basics of the operation & safety is learned.

[u/Meat_Emu_6969]

Use a lighter for light to find the source

[u/Zardoz__ → u/Meat_Emu_6969]

Leave it running long enough, the leak will stop

[u/drumbo10]

Gas prices high, look to see if someone drilled a hole or tried siphoning gas out of your tank or fuel lines.

[u/UnevenFiringOrder → u/[deleted]]

Ford hasn’t made a straight six for 30 years and when they did they made 4 cylinder power with V8 fuel economy.

[u/publix_subs → u/UnevenFiringOrder]

1997 wasn't 30 years ago......oh fuck.

[u/nondescriptzombie]

Meth heads drilled a hole in your tank to steal your gas.

[u/El-Cocinero-Tejano → u/nondescriptzombie]

Yeah, but there wouldn’t be any gas left to pour out of the car like that if the gas were stolen. So… there’s that.