I have overfilled or "top off" my fuel tank

[Battousai01]

Hi guys, I just had a brand new Hyundai vehicle and it is a gasoline one, I had it since 3 days ago.

I made a mistake by not "quickly" reading the owner's manual first specifically the first few pages concerning information about the gasoline to use and break-in instruction.

So from the dealer I went to straight to the gasoline station to put in some fuel and the very first mistake I did was to to "top off" the fuel tank. This is my first brand new gasoline vehicle and all of the vehicles I had are diesel engine vehicles. I just realized after reading and watching videos on Youtube that topping off is dangerous and will damage your "EVAP" system.

The amount of excess fuel I topped off was around 4-5 liters, the fuel tank capacity of my vehicle is 40 liters and I have topped it off at around 45 liters. Although I have not topped it off up to the brim.

After learning that we should not top off our fuel tanks, this will be the first (for gas) and last time that I will top-off the fuel tank.

Now, my question is, is the EVAP system of my brand new vehicle already compromised? Should I bring it to the service center and have the charcoal canister replaced?

 

[RLGL]

If there is no check engine light, forget about it.

 

[Battousai01]

If there is no check engine light, forget about it.

Thanks @RLGL for the reply. What I am worried more is if this one-time topping off has affected the integrity and the accuracy of fuel economy calculations and if the charcoal canister got soaked up already with gasoline, I am pretty OCD specially about the charcoal getting permanently soaked with liquid gasoline. Should I be worried about the charcoal canister and have this checked or replaced or just leave it? The vehicle is brand new and just 3 days old.

Also, I have read somewhere that there is a float valve mechanism in the fuel tank where it prevents the flow of liquid gasoline to the charcoal canister, is this true for Hyundai vehicles?

 

[RLGL]

Again, if no check engine light, forget about it!

 

[BoomerD]

OH NO! Your new car will explode! You need to have it towed IMMEDIATELY to Jiffy Lube and let them fix the problem...replace the carbon canister, change your oil, flush your transmission and radiator, and change your gear lube.


(or, just call the Hyundai dealership and talk to them....)

 

[WelshBloke]

5 litres is a hell of a "top off"!

 

[crashtech]

Vehicles are designed to deal with the occasional overfilling and/or liquid gasoline entering the evap system. If they weren't, they'd have a warranty service nightmare on their hands.

Just relax and enjoy your new vehicle, it's going to be okay.

 

[snoopy7548]

I always fill until the tank overflows so I know it's full.

 

[crashtech]

I think if gas pump shutoff valves had to meet some kind of sensitivity spec, we'd be better off, but I think all of us who have pumped fuel know that some pumps are overly sensitive while others will easily allow an overflow. This is another reason why OEMs have to make their vehicles resistant to overfill conditions, since no two pumps seem to be quite the same.

 

[BoomerD]

I always fill until the tank overflows so I know it's full.

Everyone knows this.

 

[deadlyapp]

If the fuel wasn't physically leaking out of the gas fill, then you didn't actually overfill it.

 

[[DHT]Osiris]

If the fuel wasn't physically leaking out of the gas fill, then you didn't actually overfill it.

Had that happen once on a faulty pump that didn't shut itself off, had a hell of a surprise when gas started spraying out onto my shoes.

 

[pcgeek11]

It isn't good to do this all the time. Liquid getting into the charcoal evap canister is eventually going to kill it cause a MIL Code (Check engine light). Then it will need to be replaced, $$$$. It could also damage other parts of the evaporation system.

https://www.cars.com/articles/what-happens-when-you-fill-up-with-too-much-gas-442051/

These systems are only designed to work with vapors, not liquids. If you overfill your tank, it can cover the vapor intake hole with liquid gas, which can then be sucked into the charcoal canister. This can damage the canister and possibly other parts of the system, which will cause the car’s check-engine light to come on and could potentially cost hundreds of dollars to repair.