I have a 01 a4 1.8t and when I read my dash to see my mpg that i get, it jumps from 7.9mpg to 45mpg and sometimes 165 mpg back down to just other random numbers. I had the car scanned yesterday and there wernt any codes that popped up any suggestions? o2 sensors maybe?

you get very high mpg readings while coasting. calculate your actual mpg and post it here.