I posted this a week ago in the electrical section and only have 1 reply, so I'll try it here and see if it get's more exposure so I can hopefully get an idea of what might be going on...

...2002 A4 quattro 111,000miles. Catalytic converters replaced sometime in late 2007 around 103,000 miles. Lately, the check engine light pops on - car runs fine. Have had looked at - diagnostics run (paid approx $80 each time), only to be told that nothing can be found. I've discovered that opening and closing fuel door will get the light to turn off (sometimes I have to do it with car running, sometimes before I start car after sitting for a while, sometimes it's a combination). As you can imagine, though - it's a bit annoying to have that crucial light go off and not really know if it's warning something valid (especially since it may take a few attempts with the fuel door and a couple of ignitions on/off to shut off). Car also just passed California smog test so emissions system must be okay.

Any thoughts about this so that I don't keep going in and paying $80 for a computer to tell some tech that my car is fine.... Thanks

 

autozone will scan it for free. we really need a code or something to actually diagnose. if it help i know when i bought my A4 the owner gave me a repalcement gas cap (simple replacemnts found at any auto store) because he said the car kept getting a CEL, he went back to the old one after passing smog because the factory one had notches on it to hold onto the fuel door. just my 2 cents. hope it helps. like isaid we really need a code or something and if a scan isnt picking anything up you gotta do it when the CEL is one, otherwise all we know is that teh code isnt being stored. also the feul cap issue maybe and evap leak.

 

mine i think was a fluke it was p1198 and p1199 at the same time? weird. whats that mean?

 

bump cuz i wanna know what the deal was with mine.

 

ok so thursday i ran my cars gas tank dry because of the faulty gauge, anyways after that a slew of codes came on i cleared them then got more codes on last night and cleared them today and came back on, the codes are (that i can remember)
p1198
p1199
p0300
and another one, they said that it was manufacture malfunction i believe and something about a misfire. please help.

 

you ran your gas tank dry.. that is why the code P0300..random misfire cause of lack of fuel.not sure about the P1198 or P1199

 

but i cleared them and they all came back.

 

P0300 came back then you have a misfire somewhere.. fix it first then deal with the P1198 and P1199..

 

what exactly are the other 2 having to do with?

 

well lemme know what kind of car you have year, engine and all and ill see what i can find..