Question: C6 Gas Fumes after fill up

[Luiparra]

Gas fumes

danjanuchowski,

Apologies to see you're experiencing fume concerns. I can understand any displeasure that this causes. Please keep us posted on your dealer visit and don't hesitate to reach out to us if our involvement is needed in communicating with the dealership.

Kind regards,

William R.
Chevrolet Customer Care

William
Please refer to my last visit to the dealer where they keep insisting that this is a computerized venting system that goes through a cycle every 10 - 20 engine starts. Is that a fact?
Lou

 

[Luiparra]

GAS FUMES, persisting.

danjanuchowski,

Apologies to see you're experiencing fume concerns. I can understand any displeasure that this causes. Please keep us posted on your dealer visit and don't hesitate to reach out to us if our involvement is needed in communicating with the dealership.

Kind regards,

William R.
Chevrolet Customer Care

William,
I am still having this problem. After my last reported dealer visit, they informed me that the system venting is triggered by the computer which dictates a venting cycle every 12 - 20 starts and that I should be experiencing the smell of fumes. If so, why doesn't a light on the dashboard comes on so you can leave the car outside instead of the enclosed garage? Is Jack Wilson Chevrolet in St. Augustine FL telling me the truth or are they passing the buck?

Thanks for offering additional help here.

regards,

Luis

 

[Luiparra]

Gasoline Fumes - C6

HI there,

Lets be very clear, IN NO UNCERTAIN TERMS SHOULD YOU SMELL GAS UNLESS YOU ARE FUELING THE VEHICLE.

This is a safety concern and should not be passed off. Lets take a look at how the system works.

#1, it is a system by which if fuels your engine, AND RECOVERS VAPORS FROM EVAPORATION WITHOUT VENTING TO OUTSIDE AIR.

#2, when you are fueling, you may smell a bit but MOST of all vapors are forced INTO the charcoal evaporative canister as the fuel tank fills up.

This occurs because the excess vapors in the fuel tank are forced INTO the canister because the VENT solenoid is open at the other end. As fueling occurs, the fuel seals the filler neck, creating internal tank pressure. This excess pressure is forcing gas vapors into the canister where the vapor itself is absorbed by the charcoal internals, and only air is allowed to escape. All systems presently are engineered to do this.

#3, if you shut off your engine, and you smell fuel, there are 2 options here. You either have a fuel leak or a vapor leak. Due to the fact that you do NOT have a check engine light, I am thinking that there is FUEL leaking under your car OR on the engine. This leak on the engine will evaporate before hitting the ground.

So, the tests to perform in this case are actually very simple.

#1, you can pressurize the evaporative system with nitrogen, seal the vent and purge solenoids and see if the pressure drops.

#2, you can enable the fuel pump and pressurize the fuel supply systen and see if the pressure drops.

I do agree, if the dealership says it is normal, they are full of garbage. PER EPA guidelines, this is unacceptable, nevermind by GM service standards!!!!

Allthebest, Paul

Hi Paul,
I didn't ignored you. I am with you as far as the smell of fumes, it shouldn't be. However, I specifically took the car to the dealer and it was kept for two days. They couldnt find any leaks (tank was full to the neck). No residues, no traces of gummy residue or dirt trapped in a residue, etc. All hoses and vents connected properly (so they told me), no issues other than the computerized vent system which cycles every 12- 20 starts. I don't have the capability of looking at this myself, too old to climb under it and I don't want to take the car to a "mom & Pap" mechanic or a Franchised Automotive place, they are bound to charge me for stuff I may not need and I simply don't trust them. The dealer should by all means, be the supreme word on service diagnostics. Do you think I should contact the regional Chevrolet office/Customer service?

Thank yo for your detail description and concern.

Best

Luis

 

[Chevy Customer Service]

William,
I am still having this problem. After my last reported dealer visit, they informed me that the system venting is triggered by the computer which dictates a venting cycle every 12 - 20 starts and that I should be experiencing the smell of fumes. If so, why doesn't a light on the dashboard comes on so you can leave the car outside instead of the enclosed garage? Is Jack Wilson Chevrolet in St. Augustine FL telling me the truth or are they passing the buck?

Thanks for offering additional help here.

regards,

Luis

Luis,

Thanks for your inquiry and I'm sorry to read of these concerns you're experiencing as well. Unfortunately we are not certified mechanics with the ability to provide technical advice. What we can do is reach out to designated personnel at your dealership with regard to your additional questions. Feel free to contact us privately at your convenience if you'd like to proceed, or discuss this situation further.

Kind regards,

William R.
Chevrolet Customer Care

 

[scip54]

Some goodwill reapir from dealer

Has anyone with a C6 had a problem with strong gasoline fumes coming out after a tank fill up?
My C6 coupe does it until is about 3/4 to 1/2 full, and then I fill her up again and the fumes come back when I park her in the garage.
It is very uncomfortable, I have to crack open the garage door to let the fumes out for ventilation in the garage take over. Luckily, I do have fans and a side access door which help with the air flow through my garage. I have checked the floor, and I don't see any gasoline leaks or puddles (poodles yes, I have two of them, miniature, but they don't smell like gas:L)
I was already told by another member not to overfill the tank and let the gas pump clicker do it for me, and I tried, but still smell fumes, although not as bad.
If anyone can shed some light on this problem, maybe I could get it fixed.
Thanks guys/gals

Luis

the problem is bigger than we think this is an issue w/ alot of C-6's. its a bad drivers side tank (plastic) in my case according to Chev dealership.they want me to pay $1256. and they will pay $515. My vett, an 2007 has only 59000 miles and they won't fix it under the 80000 mile emission warranty.some people say its a problem w/ plastic nozzles on gas lines and fuel pump.i contacted NHTSA and filed a complaint, this is a safety issue and EPA with gas vapors in the air.

 

[Luiparra]

Gas fumes

the problem is bigger than we think this is an issue w/ alot of C-6's. its a bad drivers side tank (plastic) in my case according to Chev dealership.they want me to pay $1256. and they will pay $515. My vett, an 2007 has only 59000 miles and they won't fix it under the 80000 mile emission warranty.some people say its a problem w/ plastic nozzles on gas lines and fuel pump.i contacted NHTSA and filed a complaint, this is a safety issue and EPA with gas vapors in the air.

Thank you SCIP54, for some unknown reason, mine has stopped doing it ever since I had some major repair done to the differential box, the service advisor said the mechanic found a vent line open/disconnected and it rarely does it anymore. If you read the email trail, you will find that there was an email from GM Customer Service that interceded and were going to do anything possible to solve my problem, but as I said, the issue kind of disappeared after the differential gear box repair (clutches were worn). My Vette is now 84K miles and we just came back from a crosscountry trip of almost 4K miles, so my warranty is already expired. If there is a recall, then they will have to fix it as with the case with the headlights on my last service, it had not been complied but it was done. Please keep us advised on this matter, it sounds like the plastic parts in the fuel system could be a dangerous and environmental problem.
Thank you again for posting your findings and actions.
LUIPARRA

 

[c4c5specialist]

HI there,

Vent line disconnected will cause your issue with fumes as they vapor is not being directed to the charcoal canister. The removed the rear subframe to get the differential out and saw the issue, and its done, that is excellent.

As for the 'major problem' with the tanks, I digress a bit here.

Yes, there have been some cracked tank cross overs and transfer tubes, but I believe its more due to technicians who attempt to remove tanks or do service work with the tanks without removing the driveline.

YOU MUST remove the driveline to service this fuel tank system, there is no other RELIABLE way to do it.

Allthebest, Paul

 

[tommyoneleg]

I have a 2006 that does the same thing but going through all the post I noticed that the C6 has a similar system to collect the fumes like my 2009 Can-Am spyder has/had. My spyder had a worse gas smell then my C6 so I removed the whole system all together and the smell went away. It seems anything that the govt demands anymore and needs it right way always has some problems.