[Z_Boy]

I made a post a little while ago about my 99 T/A A4 only getting about 22-23 mpg on the highway and was curious why it wasnt getting in the upper 20's like most people in the forum. Well i was alittle worried about my city because back then i hadn't gotten a chance to check the city. well it turns out that im getting very good gas mileage, around 18-20 in city. my question is why is my highway so ****************ty compared to the in city? shouldnt there be a bigger jump in mpg than 2 or 3? I have also noticed that i get A LOT worse gas mileae when using 93 octane vs 91 like 20 mpg highway vs. 23. could be a brand difference but i dont know. I drove back up to school last night and got around 20 mpg on a 200 mile trip but my dad filled up the tank and i dont know what brand he used. I normaly go with shell 91 octane v-power.