Abysmal Fuel Economy - Please Help

[wflan]

So I have an 07 A4 2.0T M with around 17,000 miles on it. I just got chiped but this issue has been around for at least 500 miles prior to the chip and persists after.

I'm used to getting 28-31 MPG due to a combination of where and how I drive. It's been this way until a little while ago when the MPG dropped about 30%. Now it's a feat to break 21 MPG.

EX: On the way back from Whistler w/o traffic (basically a highway that happens to drop a kilometer along the journey) I managed 25.5. I've been to the stealership twice for this and despite me very clearly explaining something's very wrong and very different, they don't seem to want to do more than check for fault codes and send me on my way (or at the least their explanations of what they did were simplistic). I even gave them a recipt for 3/4 tank of gas where I was driving deliberately conservatively and got 18.27 MPG.

What can I do personally or ask the dealership to do to fix this? In Vancouver, Premium's been hovering around $6 a gallon and I'm really ready for my low dispacement turbo four to stop acting like a very slow V8...

P.S. I've checked cursory things like tire pressure (fine)

[A4CE1]

im getting 14.8 according to my instrument cluster. im chipped with exhaust too. i consider it a win over my old chevy avalanche truck that averaged around 10 lol

[viperdsa]

I'm to lazy to crank the numbers to see what i'm getting, but the first 1/4 of the tank goes super quick for some reason.

[toaster]

i got 15mpg in my 02 a4...

audis don't get the best gas mileage...but they make up for it by owning the road.

[Brent27]

I get atleast 25 city and 32 hwy ive gotten ridiculous reads when doing all hwy at 80 mph....check filters or run some fuel cleaner or racing fuel maybe to clean it out if you run your tank bone it may have had lots of build up in it......

I had a 2000 bmw 330 and when it was idling rough the dealership told me to put a tank of "the cheap stuff in it" which i then did put 87 octane in and it fixed it.....don't understand why or how...

[AudiWxGuy]

I avg about 26.6 with mixed hgy/city. I can get about 32-35 mpg hwy, tho @ 70-80 mph.

[Quattro]

i have shitty mileage, check pcv value seems to cause a problem with fuel

-randy

[wflan]

point is that it's a sharp departure from this car's historical performance and even when i'm literally driving down a mountain I can't get figures I didn't have to stretch for previously

:/

[IceMole]

Do you have stock mode? If you do, you might want to put it to stock and see if it helps, if not you may have a vac/boost leak somewhere.

[wflan]

yeah, it started before I got chipped and isn't any better after (in either mode)

[Sharkfin]

Is your air filter jammed? That could decrease it a little...otherwise I think there are some serious issues because that's just weird

[aaron1085]

i drive 2/3 highway and 1/3 in the city... the city i accelerate slow and average around 18, the highway i cruise around 75-80 and get around 26-28... i have 19" wheels which help a bit on the highway

[INTEGRATION]

Ever thought it could be your driving style also?

And oh yeah, if you know how to read dyno charts... compare a stock dyno vs. a "chipped" dyno output. That would actually answer ALL of your concerns.

[bhull35]

I get 27.2 city and around 31 highway. Try running some Redline Complete Fuel System
Cleaner. Use a complete bottle w/ one fill up, then about 1/10 with the next several, Bottle is has levels of graduations on it. Then see what your mileage is.

[speedydragon]

I had a 2000 bmw 330 and when it was idling rough the dealership told me to put a tank of "the cheap stuff in it" which i then did put 87 octane in and it fixed it.....don't understand why or how...

that probably made the ecu change the timing for the 87 and changed it back to normal when you put in 91 or premium

[Louis J.]

Sounds like you have PCV failure: http://www.audizine.com/forum/showthread.php?t=153392

I got mine fixed at Capilano after reading poor reviews on Open Road and Richmond. See Dan Gira...good guy and took good care of me.

[Postman]

I avg about 26.6 with mixed hgy/city. I can get about 32-35 mpg hwy, tho @ 70-80 mph.

That's almost exactly where I'm at with those speeds and the mixed driving. Oddly enough it seems to drop under 70. Never driven that long though at 65, but it might actually be lugging the engine too much.

[quattro.it]

i have shitty mileage, check pcv value seems to cause a problem with fuel

-randy

+1

I see 30+ hiway all the time. Never lower than 22avg over 1000's of miles. I've replaced PCV twice and 3 of 4 coils in 11k miles.

[72mako]

I had a sharp departure from my normal mileage (6mpg drop) in the last tank. Took the car in and there is an issue with the fuel system that's going to take a few days to fix. Just waiting for them to get a loaner in this afternoon. One other point the dealer mentioned was that the car would have sounded a little bit louder due to this and he was right, it has been louder lately. My drop wasn't quite as substantial as your drop in mileage but definitely worth getting it looked at.

[Bllzll]

i need to take my car in asap

i put 40$ in.. which is about 9.5 gallons.. and after about 150 miles my car needs to go back for gas! thats like 15mpg.. that cannot be right.. i feel like even if i drive 100% city it should still be much higher

[RedS-line]

gas mileage goes downhill after 60mph. 15mpg in a 2.0t means youre either racing or the car needs servicing.

[INTEGRATION]

gas mileage goes downhill after 60mph. 15mpg in a 2.0t means youre either racing or the car needs servicing.

Depends lol. If you have good throttle control it doesn't matter, not to mention you should look at the our 2.0T's stock engine dyno again...cause according to the power output the engine gets similar mileage between 60ish and 80 -_-

[72mako]

An update on my car and it's sudden drop in fuel economy, it's apparently the cam lobe wear mentioned in the common problems thread (#4). It's going to take 15-20hrs in labor alone to repair (under warranty)... thank goodness I got a CPO. However, the benefits are that hopefully that fixes my terrible lag just after stepping on the gas (almost got me rear ended the other day while making a left turn) and I got an '08 S-Line loaner for the weekend. I like the paddle shifters and the front end has grown on me. :)

[KOU]

I just got my 2008 A4 2 days ago and my gas mileage is horrible! I really didn't expect it to be this bad. In 2 days of very very conservative driving almost HALF my tank is gone! I was thinking of taking it to the dealership and showing them?

I have read in another thread that its because the car is brand new? I hope the mpg improves because I expected better gas mileage with this car.