All modern petrol engines are fuel injected these days -- otherwise they'd still need a carburetor. FSI engines differ from "normal" injection engines in two ways:
Firstly, they inject fuel directly in to the combustion chamber as opposed to the intake manifold, therefore giving much greater control of the combustion process.
Secondly, typical FSI engines have two engine modes which are known as Homogonous and Stratified. The first is used when the engine is under load and is akin to how most "normal" petrol engines work, the second is used when the engine is not under load (usually less than half maxium engine speed), and basically works by creating a small pocket of fuel/air around the sparkplug whilst the rest of the cylinder contains just air. This means that less fuel is required without causing a missfire due to insufficient fuel/air mixture.
Make sense?
Oh, and I say "typical FSI engines" above because FSI engines such as the one fitted to the new Golf GTI don't use the Stratified charge mode at all, so in essence they are FHI engines. :wink:
Finally, looking at the
VW UK website it looks like they have two varieties -- a non-FSI 1.4 (75hp) and an FSI 1.4 (90hp). Personally though, for a car the weight of a Mk5 Golf, I'd advise you go for the 1.6 as the smaller engines will need to be pushed hard (speaking from some experience -- I have a Polo with an 85hp 1.4 FSI and for motorway journeys it can be a bit guttless).