Secondary Air System malfunction

I have a 2001 GMC Sonoma 4x4 and the check engine light is on.  The code is
P0410. This codes means Secondary Air System Malfunction. We ordered a new
air pump & new hose assembly from GM. The pump even had a new va***n
switch
with it. Check engine light right back on! So we replaced the two fuse
under
the hood behind the battery.( Max 30A & Typical 10A) Check engine light
back
on again! So we bought the two one way exhaust check valves on each side
of
the motor and the whole new hose assembly attached to it, that connects to
the air pump. Check engine light back on again! This is really upseting
me.
We can't figure out what to do to get the light to stay off. I researched
it
on the internet & have done exactly what everyone has reccommened! Can
someone out there please HELP!!!!!!! After $500-$600 I still have the same
problem!!!