Hard start and Low boost

[Brennig, Rakesh (CORP, GEAccess)]

Hello 20v'ers

Several weeks ago my chipped 1991 200 20v w/ 88k+ miles began to show a max
boost of 1.3 bar (normally 1.8 via IA III+) on the dash boost gauge.  The
car is hard to start, requiring 3-4 crankings before the engine catches.
This holds true if cold or if the car has sat for a bit but is still warm.
However stopping and restarting a running engine requires only one crank.
The idle is steady at 900rpm and the boost gauge reads .4 bar at idle.  The
AC works (Multi-Function switch should then be okay, right?).  I have not
noticed any cracked vacuum hoses.  The breather hose was the main suspect
and indeed was quite rotten on the inside but replacing it has not helped.
I am not sure what to look into next.

If anyone local would let me borrow their VAG tool I would very much
appreciate it.

Here is what I have done:

Replaced both turbo hoses from IC - Samco
Replaced breather hose - OEM
Turbo bypass valve (OEM replaced by po 4k miles ago)
New fuel filter, air filter (OEM)
cleaned spark plugs


Regards,
Rakesh
Boulder, CO