# HELP!!!!!! Check Engine light on After pumping Gas



## donikamba (May 10, 2013)

I have an issue with my check engine light: so here is what goes on After i top up my tank with premium gas and driving a few miles the check engine comes on and after i reach below half tank it goes off. Sometimes it comes on though not all the time. I took it to the VW dealer and they said its not the oxygen sensor as the code says but its coz i had bad gas in the vehicle. Bad gas in terms of high ethanol content. They said just drive the car than fill the gas with another gas. But it keeps on doing this and its been 3 months now. Has this happened to you guys? and what would be the solution? I dont want to take it to the dealer again and pay $150 for a diagnostic and etc.............. HELP


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## praneetloke (Aug 1, 2010)

Perhaps an air pocket in the gas tank? I am not sure though. Don't you have another dealer or a VW specialist shop around?


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## donikamba (May 10, 2013)

I guess my last reserve would be to go to another dealer. I am guessing there is a problem.


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## suzukirider1300 (Apr 4, 2013)

Same thing happened to me after I bought my car. Take the cap off and put it back on. Make sure it is on tight this time. Drive it for a little while (20 - 50) miles and it should go off.


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## sebasEuRo (Feb 26, 2006)

Least expensive fix to try should have been a new OEM gas cap...the CEL comes on if the gas cap does not provide a perfect seal...and yes, the CEL comes and goes in those situations also.


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## randyvr6 (Aug 17, 1999)

Are you topping the tank off to the brim when this happens?


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## usaf-lt-g (May 16, 2012)

1. Only fill your gas with the car turned off. Don't keep it running while pumping.

2. Make sure you turn the gas cap till it clicks.

3. Replace the Gas cap first.

4. *If you continue to get the random CEL or "Check Gas Cap" light... after steps 1-3 have been performed.... you need to replace your -N80- Valve. I just did this. It's a $20 part located in the engine bay (under the air filter box on 2.0Ts..... on left side of engine on 3.6 engines). * VAGCOM will indicate there's a "Small or Very Small Intermittent Leak in the EVAP system." Replace this valve, clear the code, you'll be golden.


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## Underthesun (Jan 27, 2013)

Either your gas cap isn't making a tight seal, or you are pumping gas after the pump stops itself. Which you shouldn't do, or at least I have heard so don't quote me on that part.


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## [email protected] (Sep 18, 2012)

This used to happen to me all the time and it was the gas cap seal. I replaced it with a new cap and it never happened again.


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## donikamba (May 10, 2013)

I will try your recommendations, I usually dont over fill the tank. When the pump stops thats when i stop. I tried to open the gas cap and close it but that didnt work. I will look at the cel if it needs to be replaced. Thank you all for your recommendations, I will inform you how this works out.


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## usaf-lt-g (May 16, 2012)

My money is riding on a bad -N80- valve vs the gas cap.... this is a simple $20 fix.


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## MSD (Feb 12, 2003)

My check engine light came on at 1300 miles. I thought it might be the gas cap (in NJ you don't pump your own gas), so I checked it and the tether was interfering. I thought I fixed it, but the light didn't turn off. Took it to VW and they said it was the gas cap. 

I asked if it would reset once you fix it and the service writer said "no". Is this true? Do I have to have the light reset every time an idiot gas attendant doesn't properly tighten it?


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## donikamba (May 10, 2013)

So I went to the Dealer today and they ran a diagnostic. It seems my catalytic converter is dead. So as you guys said I will not pay for it since it is still under warranty til 80K......... That would of cost me a handsome $3000.............


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## t-red_gti (May 23, 2010)

usaf-lt-g said:


> My money is riding on a bad -N80- valve vs the gas cap.... this is a simple $20 fix.


This was the fix when I had my MKV GTI. I had the gas cap light first followed by the CEL. It is a 5 minute fix.


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## MrRline (Apr 6, 2010)

donikamba said:


> So I went to the Dealer today and they ran a diagnostic. It seems my catalytic converter is dead. So as you guys said I will not pay for it since it is still under warranty til 80K......... That would of cost me a handsome $3000.............


For 3,000 bucks i'd go buy a full exhaust, get tuned, and for the hell of it throw on a water meth kit and still save 1,000 bucks....


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## DavidPaul (Nov 28, 2009)

MrRline said:


> For 3,000 bucks i'd go buy a full exhaust, get tuned, and for the hell of it throw on a water meth kit and still save 1,000 bucks....


I really don't think he has that great option.

It would be fantastic if VW would give him the cash it will take to replace the catalytic converter and let him do his thing. Unfortunately, due to many laws regarding vehicle emissions, the car has to be signed off as having the emission system repaired and 100% operational by a qualified mechanic.

Oh well, he is just going to have to wait a while longer for that custom exhaust.


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