air pump seems to be working.
how do I trouble-shoot entire secondary air system

 

Old thread, but I'll jump in anyway.

For starters, with engine and ignition off:
1) disconnect the vacuum control line from the combi valve
2) apply vacuum to it to open the combi valve
3) jumper across the pump relay to run the pump
4) feel for air flow coming out the tailpipe whenever the pump is run

With the engine running, check for vacuum/suction at the combi valve control line during a cold start when the pump is running. No vacuum there --> check the combi control solenoid valve that is tucked under the intake manifold. This was my secondary air system problem.