I noticed that my S4 was using oil, as I had to add some twice within 6
months. Also, I noticed an ever-so-slight whine during spool-up (which
differed from the usual spool-up sound) coming from what I thought was
the passenger side of the car. The dealer checked it out and diagnosed a
blown passenger side turbo. Both turbos were replaced under warranty by
*This is a 2001.5 S4 and is unmodified with just under 22,000 miles.