Catalytic convertor bad at 65k? PLEASE HELP !!!! on 2005 Audi A4 Quattro

05 quattro v6,purchased at 50k,exhaust tone and mileage went way down after about a month,started hard shifting and hesitating,i thought it was a transmission problem,took to local trans shop they said -it needs a rebuild for 7k! could not supply a specific explanation -worn out on the inside was all i got from them.i started it today and it was running like absolute crap at idle and 40-50 mph baaad hesitation ,i swear it sounds like bad catalytic convertor. at idle it was clearly almost backfiring -sounded like inside the cat,low sound,can anyone help me out?im a single dad with no income -is it the cat? already? and shouldnt that fall under the 80k federal catalytic warranty?thank you all

Asked by for the 2005 Audi A4 Quattro
1 answer
seems like theres alot going on with the car. are you able to have the eng and trans checked for faults? cats are covered for 8/80 if that is your problem but keep in mind cats usually dont die this early, they get killed! have you had any flashing check eng lights? a misfire can kill a cat (flashing lt). has your gear shift display lit up unusually? this would indicate a trans fault. and is your car an early 05 (3.0 v6) or late (3.2 v6)? normally i would suggest unbolting the cats and run the car to see if it frees up but on your car that ain't no picnic!!!