I joined the lr4x4 forum some years ago when I had FL1s so I still get odd messages. This, however is a very interesting case of a turbo hose on an FL1 which split inside causing a balloon to be created which restricted airflow whilst the hose looked OK from the outside. Something to be aware of when chasing problems on any turbo engine.

http://forums.lr4x4.com/topic/100516-2002-...-problems/ 3 x FL1 2 manual + 1 auto
5 x FL2 4 manual + 1 auto
Now Discovery Sport P250 MHEV SE

This used to be quite common on the D2 where the hose would de-laminate inside and as you say restrict the airflow .
Can be quite difficult to diagnose.
I guess this is why a lot of people fit silicon hoses. Martyn

2010 Sport LE Auto

had than on a defender years ago, was as flat as a fart At work
At home

"I can't always believe facts I read on the web" - Charles Dickens

winner by default of the tractor vs caravan race

In my experience (especially from my teenage sons) farts can be anything but flat. Quite high powered in fact.  3 x FL1 2 manual + 1 auto
5 x FL2 4 manual + 1 auto
Now Discovery Sport P250 MHEV SE