Alec1278

I just bought an audi 2000 2.7t A6 quattro and it didnt come with a user manual. What type of fuel does it take? I have been putting in 89 octane, the mid premium fuel.

the_duke

Premium.

georgeb944

I use 87 octane regular... it costs me about 20 horsepower, but I have suffered no ill effects after more than 200K miles of using a cheaper fuel. The only time that I miss the extra power that I would get from premium is pulling away from a toll booth, and I don't do that much anymore.

betito

use 91 cus I use the middle one and it cost me 600 to change the oxygen sensors..

Alec1278

Im still gonna use the 89. The o2 sensors wouldn't go bad from using 89. That would be a different cause. You could have just cleaned it with a cleaner for 10 dollars.

SloopJohnB@mac.com

Probably says 91 (R+M)/2 which is the unit used in the US.

93 can help if you've got carbon deposits in chamber, top-shelf fuel keeps the intake valves clean on port–injected engines.

1stGOAT

91 to get rated horsepower
89 can be used safely, ECU will retard advance to protect the motor just fine. You just won't get rated horsepower.

Octane rating has nothing to do with clogging up your O2 sensor. Also they typically do not all go bad at once but they can wear out over time.

Alec1278

If i put 93 octane in my engine will it increase the horsepower more than 91 octane? I seen a dyno on APR tuning website of that.

Ellis Rogers

I have a 98 A6. During the summer when its hot I run premium (93). During the winter because of the cold you can get away with running midgrade. This is because they blend the fuel differently (summer blend and winter blend)

jcman

Nope, just kidding

91 in the winter and 93 in the summer too.