CHECK ENGIN LIGHT ON on 2002 Audi TT Quattro

HI.I JUST BOUGHT A USED AUDI TT 88000 MILES.WEEK BEFORE CHECK ENGINE L CAME ON CODE P0171SYSTEM TO LEAN BANK1.EXHAUST SYST-FUEL PRESSOR REGULATOR-INTAKE SYST-OXEGENESENS-VACUUM LINE-SECONDARY AIR INJECTION SYST.I NEED SOME ADVICE WHAT THE CAUSE THIS CODE MIGHT BE.WHAT TO PUCHASE?THANK YOU

Asked by for the 2002 Audi TT Quattro
Tomi, Do not know exactly what the code means, but I have a 2008 TT and got a couple check engine lights in my 60,000 miles... When that light comes on, it is a good warning to get it checked by a certified mechanic or your local Audi dealership service department. My last check engine light had to do with a faulty diverter valve rupture, thereby, not giving me turbo boost. I have had three Audis in the last 8 or so years and just know this is a sign that can mean many things, and it is better to not drive the car and get it fixed ASAP. Tell me how it goes.