I've heard of this problem before. The 1.6 was wowefully underpowered when first made so many early companies offered an aftermarket solution. Look under the bonnet to the right of the block. Down behind the gearbox you shouls see a small round cage.
If you look you should be able so see a small brown or yellow furry thing.
Your aftermarket turbo is squeeking because it is hungry. Give it some nuts and all should be well.
