[A4] Need for Premium Gas in 1.8T quattro?

[Brizax at aol.com]

true
 
the only other thing i would worry about is that your running synthetic  oil, 
this might not help the sludge situation on the 1.8T

Absolutely you can run mid-grade or low-grade fuel.  I've been  
running 87 octane fuel in my '01 A4 for 190,000 miles.

The car is a  bit down on power under full-throttle acceleration, 
but not enough to  really notice unless you were on a dyno or at a 
drag strip.  (FWIW,  I've seen the ECU pull out as much as 4 
degrees of timing due to  pre-ignition.  Not all that much, really, 
but enough to put you about  10-15HP down.)

Fuel efficiency is NOT drgraded and you are NOT wasting  fuel!  I 
get 33mpg on the freeway and 29-30 in town -- have been  since '01.