[Qatar_Speed]

Hello,

I was out with My friend and his Aventador SV and we stopped at a petrol station to get fuel. After driving the car out of the petrol station the engine check light came on and we stopped on the side of the road to check what is wrong with the car and we realized that the fuel cap was not closed properly after refueling the car.

Does the fuel cap in such cases causes the engine check light to come on ? .. If so what should we do in such situation because the car drives normally without any problem and we are wondering if we should take the car to the dealer or not.

 

[XSNRGY]

Hello,

I was out with My friend and his Aventador SV and we stopped at a petrol station to get fuel. After driving the car out of the petrol station the engine check light came on and we stopped on the side of the road to check what is wrong with the car and we realized that the fuel cap was not closed properly after refueling the car.

Does the fuel cap in such cases causes the engine check light to come on ? .. If so what should we do in such situation because the car drives normally without any problem and we are wondering if we should take the car to the dealer or not.

Um, the cap doesnt come loose by itself?
Once you tighten it,shouldnt that be the end of it?

 

[AngelOfMurci]

I realize that my Murci isn’t an Aventador,
But my gas cap is unlocked via a dash gas cap button. So when i physically close the gas cap, a sensor is detected and locks the cap.
Does an Aventador have a dash button to lock/ unlock the cap? If so, try pressing the button. Also, make sure the cap is in correctly and that there isn’t a sensor that’s jammed.

good luck

 

[AngelOfMurci]

Just to clarify my setup on the Murci

my cap has a little rod that retracts when it’s unlocked
It will extend into the cap to lock it

if the rod doesn’t extend properly, my dash light will come on.

good luck

 

[XSNRGY]

I realize that my Murci isn’t an Aventador,
But my gas cap is unlocked via a dash gas cap button. So when i physically close the gas cap, a sensor is detected and locks the cap.
Does an Aventador have a dash button to lock/ unlock the cap? If so, try pressing the button. Also, make sure the cap is in correctly and that there isn’t a sensor that’s jammed.

good luck

 

[CFI Designs]

Never seen this before, usually a few miles after correcting these kind of lights go away, buy a VCDS Ross tech tool it works well on the aventador and probably save you many trips to the dealer.

 

[BRU]

I had the same issue with my AV S. Didn't tighten the gas cap tight enough and the check engine light came on at some point. Tightened it up, used an ODB II scanner to clear the code, light went off. Your car should be fine.

 

[XSNRGY]

I had the same issue with my AV S. Didn't tighten the gas cap tight enough and the check engine light came on at some point. Tightened it up, used an ODB II scanner to clear the code, light went off. Your car should be fine.

Isnt that bizzare?
So there must be a pressure sensor in the fuel tank for this to bring up the CEL.

 

[AngelOfMurci]

Isnt that bizzare?
So there must be a pressure sensor in the fuel tank for this to bring up the CEL.

FYI, on my Mitsubishi SUV, an engine light will go on if the gas cap is loose or not on tight. That’s because the fuel system is based on fuel pressure that the return lines and fuel delivery are supposed to create. The system detects vapor pressure leaks. I’m pretty sure it’s not a big deal, except in extreme circumstances that create vapor lock???? Maybe???

 

[BRU]

Isnt that bizzare?
So there must be a pressure sensor in the fuel tank for this to bring up the CEL.

My mechanic friend said many cars have this feature. Just gotta make sure we hear the clicks when tightening the gas cap. I was lazy once, never again.

 

[XSNRGY]

FYI, on my Mitsubishi SUV, an engine light will go on if the gas cap is loose or not on tight. That’s because the fuel system is based on fuel pressure that the return lines and fuel delivery are supposed to create. The system detects vapor pressure leaks. I’m pretty sure it’s not a big deal, except in extreme circumstances that create vapor lock???? Maybe???

This is news to me and I'm shocked really.
Worked on cars for a long time including when Snap On scanners came to NZ and don't remember anything mentioned about this.
Mind you I'm an old bugger now so I'll blame my memory

 

[AngelOfMurci]

This is news to me and I'm shocked really.
Worked on cars for a long time including when Snap On scanners came to NZ and don't remember anything mentioned about this.
Mind you I'm an old bugger now so I'll blame my memory

I know for my 71 Dodge Charger, the gas tank has 3-4 incoming out going lines. They allow vapor from the carb and valve covers to go to a charcoal condenser and then return back into the gas tank. A couple reasons for it. First, it recaptures gas vapor and keeps it in the system instead of letting it go into the atmosphere. Second, without pressure or a non sealed fuel system your tank would slowly go dry via evaporation AND your garage would filled with a massive amount of fumes(dangerous). On my Charger, there’s a special gas cap that has an 0 ring that seals the cap, but will open/pop up if the tank exerts too much pressure.

anyway, I realize these exotics are designed entirely different from carb old school cars.
that’s why I had lots of question marks in my initial claims.

would like to hear from certified mechanics on this issue.

 

[surfah]

I know for my 71 Dodge Charger, the gas tank has 3-4 incoming out going lines. They allow vapor from the carb and valve covers to go to a charcoal condenser and then return back into the gas tank. A couple reasons for it. First, it recaptures gas vapor and keeps it in the system instead of letting it go into the atmosphere. Second, without pressure or a non sealed fuel system your tank would slowly go dry via evaporation AND your garage would filled with a massive amount of fumes(dangerous). On my Charger, there’s a special gas cap that has an 0 ring that seals the cap, but will open/pop up if the tank exerts too much pressure.

anyway, I realize these exotics are designed entirely different from carb old school cars.
that’s why I had lots of question marks in my initial claims.

would like to hear from certified mechanics on this issue.

Just had my Huracan in for 5 year annual and the charcoal cannister was replaced. Had to wait over 1 week to get part shipped to dealer and it cost over $900 USD. Lambo tax

 

[surfah]

Just had my Huracan in for 5 year annual and the charcoal cannister was replaced. Had to wait over 1 week to get part shipped to dealer and it cost over $900 USD. Lambo tax

Strange SA quoted $900 for charcoal canister but I was charged $388 plus $75 freight. Pleasant surprise.

 

[XSNRGY]

Strange SA quoted $900 for charcoal canister but I was charged $388 plus $75 freight. Pleasant surprise.

Wow, you will be happy with that!
There are a lot of similarity with Audi products, maybe not so much on your Huracan but it pays to google or come on here and look for parts as someone always finds something for their car at a way cheaper cost than the genuine Lambo-tax extortionists charge us.

 

[boatpi]

In many states the emissions warranty covers any emission failure for up to 7 years.

 

[surfah]

Wow, you will be happy with that!
There are a lot of similarity with Audi products, maybe not so much on your Huracan but it pays to google or come on here and look for parts as someone always finds something for their car at a way cheaper cost than the genuine Lambo-tax extortionists charge us.

Thanks and good advice.

 

[lamboandre]

same happened with my Aventador, a bit sloppy when tightening the fuel cap and the check engine light came on. Tightened the fuel cap and erased the alarm with OBD, all good. Think its part of EVAP regulations to avoid pollution actually..... Btw, also did the charcoal canister on the Aventador recently, USD 1700 bucks.... they mentioned there was an upgraded purge valve also, but difficult to check those facts....

 

[surfah]

Damn that’s pricey. $388 for the H charcoal canister seems like a deal.