im not sure which could be the reason but thursday i ran my cars gas tank dry because of a faulty gauge going full and empty and in between, also the day before i got a custom cat back done all the way up to the dual cats.

now after i ran my tank dry i got engine codes, to be expected obviously, cleared them and it was fine, then last night they turned on and it said i have 11 codes but i think most were repeated. codes such as:
p1198
p1199
p0300
and something about a manufacturer malfunction or something like that, i got them cleared, drove a few miles and it came back on. what can this be from?

please help me asap i just bought this friggen thing

BTW i dont seem to have any issues with the car it feels fine i dont feel any hesitation or bucking or anything.

 

http://www.obd-codes.com/trouble_codes/audi/

 

1198 and 1199 are o2 heater circuit. if a circuit is bad clearing the code wont fix it.
i would guess bad cats or o2 sensors. but that's just what i found when I USED THE SEARCH BUTTON!!

 

the 1198 and 1199 one was something about a radiator and the other was the exact oposit about that radiator.

 

Where did you get this information from? Sounds fishy to me.

 

there are no codes pertaining to the radiator whatsoever, whoever gave you that info is wrong. can you post up all the codes you have? it'll give us a better picture of what might be wrong. you probably have fouled out your injectors though, fuel system cleaner will do the trick and seafoam will too

 

the codes i got that i can remember were the 1198 1199 and 0300 there was 11 so i dont remember them all but i can try and get them, any ideas off of those ones?

 

http://wiki.ross-tech.com/index.php/Main_Page

put the codes in the search box, this will give you a better explanation

 

yeah problem is the car feels fine.

 

no the problem is- we need all the codes so that we can figure out which are related and which are just normal things that need attention. also when asking for help, if you took the time to post the code and what the code means (from here
http://www.obd-codes.com/trouble_codes/audi/ , among other places) that is less work for the people helping you, and you will more likely get an answer. il tell you im not going to sit here and search for the definitions of 11 different codes and then figure out whats wrong with some random guys car on the internet.