WGFV testing procedure... (200t overboosting)

[Gerard <gerard@poboxes.com>]

Hi!

Some of you might know that my 200t has started  overboosting. I
suspect the WGFV is either stuck or buggered. I need to test it and
would like to know the procedure for doing this.

What happens is that the boost on the car can build up quite rapidly
and I can't determine what the problem is. It might be the WG is
being held close by the FV if the FV is constantly letting air through
to the back of the WG. The car never boosted more than 1.1 bar here
at altitude, but it is no hard task anymore to see 1.5 come up on a
car limited to 1.4 boost and 1.6 overboost. Could it be the FV
causing this to happen? Or is it a problem with the turbo itself?

At the coast the boost never went over 1.3 and that was with me
nailing the throttle  heavily. Now it takes little over half throttle
to see the boost build up fast. I checked the fault codes after a
normal drive (avoiding fuel cutoff) and there are no problems
reported (4444 code).

I removed the cover of the WG and found a small piece of either soot,
dirt, plastic  or rubber (about 1mm in size, a little smaller, but I
think this is just rubbish from the intake anyway). The rubber seal
that fits between the cap and WG housing and is attached to the moving
part of the WG is torn along the lower (gearbox) end. The WG spring
looks fine and the WG slips back into place without any resistance.

What is the test procedure for the WGFV that will enable me to narrow
the problem to the WG or the FV?

G.
-- 
"a thousand miles from here, there is another person smiling"
1990 Turbo (200T)
name   : gerard van vught
tel    : +27-57-912 2658 (w) / 082 923 9609 (cell)
url    : http://www.acenet.co.za/homepages/gerard/
e-mail : gerard@poboxes.com  / han.solo@galaxycorp.com
         gerard@acenet.co.za / van_vught@frg.issi.co.za