hi all i just picked my 04 fabia vrs and on way home i put my foot down and when it got into high revs in boost it just slowed down and woukdnt boost again so i turned car off and on an it works fine till you put it in boost and does the same thing i plugged it to a machine and it said underboosting or something has this happend to anyone before any help would be great thanks.

It sounds like the engine is going into limp mode. It could be the 'sticky vanes' problem with the turbo.

Thanks mate is it a easy fix or is it end of the turbo sorry mite be simple but i new to fabias cheers

A few on here swear by spraying mr muscle oven cleaner into the exhaust side of the turbo to cure the sticking vanes.