our cars suck when it comes to gas consumption lol but its ok when not in boost but i have a dilemma.
today i filled the tank to about 3/4 full 250miles to empty etc i looked at the guage tonight at midnight it says 100 miles till empty and the needle is between 1/2 and 1/4. i only drove 50 miles and didnt boost it one bit so anyone got any ideas cuz that kinda mileage sucks. ive done all the cleaning for it and the normal fuel system cleaning oil change maintenence. i do have a brake light switch code popping up so please any ideas thanks

 

that is weird, i dont know , i think we have GREAT MPG on the b5 s4 its better then my girls stock 06 c280 4matic and i used to have a 2.8 b5 a4 and i think the b5 s4 is better on gas.

 

The in car calculations can be off by +/-3 mpg or so iv heard. My gauge can be a little wacky sometimes, iv had those "i thought i had way more gas than this" moments

calculate it yourself, how much gas you put in and on the odometer how far you go then see if it makes sense.

3/4 full = 12 gallons

250 miles/ 12 gallons = 20 mpg

20mpg = 320 miles per full tank

^ that all sounds perfect

halfway between 1/4-1/2 full = ~6 gallons

100 miles/6 gallons = 17 mpg

17mpg = 275 miles per full tank

Neither one of those readings seems terrible, but i guess the time inbetween that your worried about.

If you think somethings wrong, maybe your fuel tank sender is going bad and the car thinks theres less fuel in there then there is. Or maybe a bad MAF or something is causing you to get bad mileage..

 

That "miles until empty" reading is always off - I wouldn't go by that. As others say, just do the math yourself.

 

i drove to the drag strip last friday, and even it was closed on the highway i was between 85 mph to 120 mph the whole way and when i filled up my estimater said 410 till a fill up.. so thats pretty good mileage..

 

thanks guys ya it makes sense now it was just one of those weird feelings i guess lol

 

i know the feeling, i have a faulty gas reader..whenever i fill up it says 3/4 of a tank and it wont go up to full till about 15 minutes later... kind of annoying but i do the math everytime i fill up and im getting about 22-26 average depending on my driving style. the worst i've had so far is 20mpg but 17 could easily be accomplished with constant boosting or stuck in traffic, i hardly do any city driving tho so i get a little better.