(Another) failed transmission?

I previously posted this request on the Yahoo svxclubuk group (http://autos.groups.yahoo.com/group/svxclubuk/) messageboard. One of the responses suggested I should try here because you are more technically minded! So here goes but please note both the car is in the UK.

I have recently suffered a slowing of my 1992 SVX after the engine car warms up. It is perfectly OK when cold but after say 15-20 miles into a journey the engine is slow to build revs when accelerating from low revs. It feels like it is in a high gear but I get the same effect if I pull away in manual/first. The Power light comes on until about 3,000 revs (sometimes 4,000) after which the performance is normal. On start-up the Power light stays lit for about 2 seconds, it then flashes for a further six seconds. So eight seconds after the engine starts the Power light is extinguished.

I have gone through all the wire connecting and gear lever shifting/button pushing and discovered the following faults:

Engine
32: Qxygen Sensor
28: Knock Sensor.

Transmission
24: Duty Solenoid C
32: Vehicle Speed Sensor 1
33: Vehicle Speed Sensor 2

Would I be right in thinking that the engine faults are unlikely to cause this behaviour? If so then on to the transmission where the faults look more hopeful. The solenoid fault surprises me because all gears can be accessed both manually and appear to also be accessed by normal driving and kickdown. The Speed Sensors sound like the likely candidates or could the problem be causing them to appear at fault if that's possible.

Does anyone have any idea what the fault might be and does it mean a full strip and rebuild of the gearbox or is there a possible less drastic solution? My local Subaru dealer has advised that one or more of the clutches is slipping and causing confusion within the electronic management system. Does that sound a sensible prognosis?

All input gratefully received.


David Caple