Jnjrowland

The fuel door and the manual seem to be a bit contradictory. The manual suggests 91 is better while the fuel door suffices with 87. For the few cents a gallon in the difference I believe I'll keep feeding it 91 or better.

ionian2k

"Recommended" is not same as "Required".

Porsche70T

Carefully check the filler door.. The rating for Europe is RON not CLC like here.. Translation 91 RON is our 87 octane. 95 RON our 91 Super/Premium.

a2oc

a bit off topic, i saw there on the mk7 golf 1.8t (same engine as our 1.8T a3) says 170hp is achieved by premium fuel. Tried once on a 87 diet on my a3, I regret it so much I would not put 87 anymore in it. There is no power across the rev range and its dog slow, although it does not knock. Since that, 91 diet only for my a3. Even if I dont drive it like i stole it, I can still feel the difference between 87 and 91.

Timmay

My philosophy has always been to put the highest octane fuel possible which of course is determined by which state you live in. I will assume an Audi owner can also afford to pay the extra for Premium fuel and not go cheap with regular unleaded. There's no reason to use unleaded gas in your Audi.

rdA4WtQ5

Our A3 doesn't run that different if regular 87 is mixed with 93 half and half. Straight 87 runs but less smooth and peppy.

Timmay

But why on earth would you even bother to mix??

rdA4WtQ5

Not that hard just alternate and fill when near half.

Timmay

Yes, my question is WHY?

rrwood

Exactly! People come up with some interesting theories. I don't always do what I'm told, but I never saw any reason to put anything other than what the people who engineered it say it needs. For a few bucks?