200tq problems

[Barbera <barbera@twd.net>]

I'm still having bad power loss in my '89 200tq.  I took the advice of
one someone and replaced the intercooler hose.  It didn't make any
difference!!.  The car still looses a lot of power when under load. 
Does anyone know what the problem could be?  This problem has had me
stumped for months, and I can't figure it out.  Could an old o2 sensor
be the problem?  If so, where can I get one at a reasonable price?  Any
feedback would be greatly appreciated.