Torque steer and low boost

[Tony Guttmann <tonyg@ms.unimelb.edu.au>]

Dear Quattro group,

I'm new to this group, so apologies if if this is a familiar
query, but my archive search was unsuccessful.

I have an '89 200 Turbo (NON-quattro - unfortunately, they never
came to Australia). It's got 90,000 miles (140,000km actually)
on the odometer.

When I bought it from a dealer recently, it suffered from
horrible torque steer. Taking off from the lights had to be done
gently or I'd leap into the lane on my left! Since then I've
experimented with tyres (no effect) and had a second wheel
alignment of all 4 wheels. This has improved matters a lot,
but it still leaps to the left on wet roads, or suitably
cambered roads. Any cures apart from selling the car and
buying a quattro?

It's second problem is low boost. Can't get above 1.3 or rarely
1.4 on the dash guage. 
(i.e 0.3 or 0.4 atmospheres of boost).
My mechanic says that I'm getting basic
boost, but that the boost control valve is getting no signal
from the computer, so I'm not getting additional boost.

Any suggestions other than a new computer?

Many thanks,

Tony Guttmann
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