markinarch

I bought a 2011 A4 PPS Quattro with the 8-speed automatic about 2 months ago. I drove it on a 300 mile trip the first weekend I had it and averaged 37.5 mpg. I was really pleased with its highway mpg and still am very pleased with the highway mpg - still averaging about the same. The city mpg is another story. I only have a 7 mile commute downtown to work everyday and I usually don't get much over 30 miles per hour. I average around 17 mpg city and 22 overall.

What are you averaging with the 8-speed?

dpcompt

keep your foot out of it when in town!!! otherwise, enjoy the car.

myriadshalaks

you should be doing better around town. it may improve over time.

SFV A4

Sounds pretty accurate. Slow city driving will pretty much kill any projections. However, getting 37 on the highway puts you way ahead of the game if you look at the whole picture.

khmerguy978

are you basing these numbers from the car's reading or doing the math yourself? the car has always been about 10% optimistic for me. regardless, those are great numbers.

markinarch

I was just using what the car told me until a couple weeks ago when I started doing the math.

How about gas type? I know Audi has their recommended "Top Tier" gasoline that they say we should use but is it necessary. All of the Top Tier gas stations I have seen only have 93 octane and I would like to save a couple cents a gallon with 91 octane. It would help a little when I do my occasional romp on the gas pedal and can see the gas needle moving down.

tgdA4

If 93 gives you the best MPG wouldn't the savings of using 91 be negated since you can go farther on the 93?

Also, you are driving a luxury car...you can't afford the extra 50 cents per tank or so to have it run on the best gas?

markinarch

No its not really the cost of the gas because it would seriously only be like 50 cents as you said. Its more that the "Top Tier" stations are out of the way from where I live.

I'm not exactly sure how gasoline octanes work because my previous car only needed regular. Does 93 give better mileage than 91? I know 93 gives better performance which is always welcome.

Thanks for the comments.

Brian Cecil

The only thing octane ratings deal with is the amount of pressure in the combustion chamber the gasoline will tolerate before it detonates on its own, resulting in a condition called pre-ignition, pinging, or knocking. Higher octane ratings mean the gasoline will withstand more pressure and delay the onset of pre-ignition. Lower rated gasoline withstands relatively less pressure, and will begin pinging earlier.

With electronic engine control modules, which vary engine operating parameters according to a large number of variables, including gasoline octane, you possibly could get more efficient engine operation with 93 octane, but probably not. Maybe you should try out the 91 gas for a few tanks, then try the 93 gas for a few more, and see for yourself what happens. In Southern California, the "Top Tier" premium gas is 91 octane, by the way.

tgdA4

Top tier has nothing to do with octane. It refers to a list of gas stations that do not use low quality detergents in their gas, which lead to deposits (which rob you of performance).

With a turbo engine you definitely want 93 when you can. 91 won't hurt it, but its not the best. I recommend Shell.