hello everyone i am new to this forum and this is my first audi i commute to school so i do a lot of driving. my check engine light came on yesterday (1/30) and it had me worried. i went to auto zone this morning (1/31) to get the codes and there were 5 codes this happened out of no where i was wondering if anyone can give me some feedback on what i should and probable causes of the issues. thanks
the car is 1999 audi a4 quattro with 74k miles

p0327- knock sensor 1 circuit or short circuit condition
p0411- air injection system incorrect flow
p1141- calculation cross check range/ performance or open or short circuit condition
p1127- long term fuel trim b1 system too rich or maf
p1129- long term fuel trim b2 system too rich

thanks for your help

 

First step is to clear the codes and see which, if any, come back. If you got it recently, some of those could be old codes. If the CEL comes back on, scan it again and see what comes back. Then you will know what to troubleshoot.

 

The cel turned off by itself but the car is lacking power.

 

If you haven't actively cleared the codes, they should still be tgere. Clear them and see what happens.