dimagavr

Hi,

I just recently bought 2010 A4 2.0T with 23,500 miles on it. And right from the go I notice that the gas consumption just goes down the drain.

I started to record actual miles driven and amount of gallons I fill it up with. So, for a quarter of the tank which is about 4 gallons, I only had about 60 miles driven. That is 15 mpg!

Since the car is under the warranty, I took it for the service. They replace high pressure fuel pump that was leaking gas into the oil and reset the computer.

Now, it improved slightly giving me about 80 miles on the quarter of the tank on the freeway which is about 20 mpg. The same 20 mpg was confirmed by filling up gas and dividing actual miles driven by the gallons bought.

That is ridiculous!

My question is this - does anybody know what else could be the problem and how serious it is? What is the realistic MPG expectations for that car giving that I am not "pressing the pedal to the metal"? And should I get rid of the car right away?

Thanks in advance!

Nostromo

I'm getting 26-28.6 MPG per tank commuting in LA. That involves lots of slow highway driving plus occasional WOT spurts when the coast is clear.

uberwgn

Hi, and welcome aboard!

Don't try to measure fuel consumption via the gas gage...huge error there and the gage is not linear. My '11 car comes off the Full mark quickly. Measure your consumption over a longer period of time. The only valid method I know of is to divide the miles traveled by fuel consumed

Does your car have the readouts showing MPG, etc? If so, that gage can be calibrated with VCDS but you need to have some history to validate.

I just returned from a 2,000 mile trip. I was getting 32-33mpg on the highway. I typically do right around 24.5mpg in the city during warm weather, somewhat less during the winter months. My car is the 8spd auto.

dimagavr

That is exactly what i did - the fuel consumed was shown on the receipt from the gas pump and the miles traveled were always reset to 0.0 when the tank is full. So before the fix, I had 222.5 miles traveled and 13.739 gallons pumped in (not the full tank), so that gives 16.19 mpg. At that time, the quarter of the tank mark on the gauge was reached at around 60 miles.

After the fix, 269.2 actual miles were traveled and 13.151 gallons were pumped in = 20.5 mpg. This time the quarter of the tank mark was reached at around 80 miles - driving only on highway. As in I filled up the tank right before getting on the freeway!


It does have all of this in the computer, and it shows average of 22 mpg. However, even if you discard the computer, the gas is being consumed too fast even visually while driving. You are getting more that 30 mpg on the highway which is about right for this type of car. 24.5 mpg in the city sounds right as well, but not 20 on the freeway.

I think I got plenty of history to see that there is something wrong - the question is to keep the car having Audi fix it or let it go.

Thanks!

Macallan21

Fuel was leaking into the oil.... how?

dimagavr

Here is what they told me: "Find strong gas smell in the engine oil. Removed high pressure fuel pump. Visually inspected fuel pump. Find signs of internal gas leak to the lubrication system. Remove/replace high pressure fuel pump."

Anyways, I am taking it to the dealer tomorrow demanding further work, because it is obviously not fixed.

Thanks.

Macallan21

OP, I do not doubt that is what they told you.

I'm just not sure how that happens without your engine misfiring. Fuel goes into the cylinder, and unless if the seals on it are blown, how does some unburned fuel get up past the seal to leak into the oil. I'd think you'd make some horrible noises, and throw a Check Engine light... that's just me.

Either way man. I have a 2.0T from 2009, and I get 33-35 mpg highway, and about 25-29 in city driving. And I feel like I have a lead foot.

Mine's also a quattro. You should be seeing similar numbers when all is right with the car.

What kind of fuel are you putting into it? 91 or 93 octane?

dimagavr

I am putting 91.

So you are getting about 120 - 140 miles on the first quarter of the tank?

Macallan21

That sounds about right, but I rarely fill up at 3/4 tank full. I cycle from Full to 1/2, and I'll check my mileage against what I fill up.

anonymous_1

try throttle body cleaning and maybe fuel induction system cleanup.. throttle body cleaning most likely would be just enough..

had similar issue.. after the throttle cleanup.. am averaging about 350miles per tank from mid 200s.

took several visits to the dealership before they figured it out(actually not until i complained about a totally different issue)..