do i also need to change water pump with it
when do i need to change timing belt on my audi tt on 2005 Audi TT Quattro
They recommend at 75,000 miles to have it replaced. You can since you are already in there and it wouldn't hurt to do so but, choice is yours if it isn't bad.
THESE ARE BOTH REC DURING THAT SERVICE ALSO REPLACE DRIVE BELTS AND COOLANT