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Discussion Starter #1
Does the Eos have a fuel cap warning light? My manual (which covers many models) has one shown, but I do not see it on the dash.
 

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Do you mean the flap open or the cap left off? You have a States model with charcoal cannister and tank vapor pressure monitor. I don't have that junk, but I thought if you left the cap off or loose and drove the car you would get an emissions warning?
 

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Not sure if my 2014 has a dedicated fuel cap light or not. I know some US market vehicles will throw a CEL for a gas cap warning. In those cases I believe the CEL clears itself once the cap is tightened.
 
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Discussion Starter #4
Not sure if my 2014 has a dedicated fuel cap light or not. I know some US market vehicles will throw a CEL for a gas cap warning. In those cases I believe the CEL clears itself once the cap is tightened.
And that was what I am wondering. I also wonder what the code would be on a leaking fuel cap. I don't think that is the issue I have been having the CEL come on with a P0420 code or VAGCOM 001056 code, but it does make me wonder.
 

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just yesterday i forgot my fuel cup open and i saw it from my mirror while driving and i had no light on the dashboard so probably does not have it
 

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Code P0420 is an emissions warning for a bad CAT (or O2 sensor?) which I don't think would be related to the fuel filler cap or flap? What are your CO emissions from the tail pipe?
 

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They can easily add a switch or sensor to the fuel flap, but the screw in cap is a different story because they must use fuel tank vapor pressure and a pressure sensor which is part of the USA closed tank venting system. I wouldn't expect an immediate dash warning of cap unscrewed. They will allow time for fillup at a gas station and after key on. They will probably base the dash warning popup time on the length of time the fuel pump has run to produce a small tank vacuum after after key on. You could test it by keeping the engine running after a trip, then unscrew the fuel cap and I would expect the warning to show? I'm pretty sure the fuel tank closed venting system will be included in vcds diagnostics and there will be a measuring block to read out detected tank pressure. If it measures zero after running when the light comes on, you know there's a tank air leak or bad component somewhere? EU cars are simply vented to atmosphere and should not have that system or dash warning.
 
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