FSI = Fuel Stratified Injection.
Have a look at this:
http://www.volkspage.net/technik/ssp/ssp/SSP_337.pdfIt states: "The new FSI engines from Volkswagen
do without stratified injection and place greater emphasis on output and torque. Until now, FSI direct injection was always associated with stratification. On the turbocharged engine, the abbreviation FSI remains but there is no stratified charge.
Doing without fuel stratification and NOx sensors represents a loss on one part, but also promises the finest driving enjoyment with high output and a torquey engine and great pulling power and economy."