Were tests done at idle and 2500 RPM or moving test on rollers?

It would help if you could post your entire test results.
The NOX and HC values and speeds/RPM will help determine the best
course of action.

Everyone;
If you have "smog test failed" questions; please post your entire
test results to get quality answers from the list...

>my EJ22 van has failed emissions (CO too high) several times in a
>row.  after confiming that the van is in tune and running right (new
>O2 sensor, valve position sensor, temp sensor and new plugs), and
>adding a test take-out before the cat, my mechanic believes that the
>problem might be that my fancy