got codes? okay so i got codes!! Howa bout p0102, p0154, p0420, p0430, and p0174. What to do? The car is a 98 z28 a4, slp cold air pack, slp maf w/ bellow, mac mids, ory, and slp lm2. Start firing at me guys plz!! this a daily driver and weekend street car so i need help.

 

stickies are your friend

if you check out the stickie about ses codes, you will find all of these in there, thats all i did. i know nothing about codes but by your list it looks like, you have maf problems, o2 problems and catalytic converter problems, the latter one is obviously cause you have an off road y pipe.