Not sure how much help this will be, but:

HC=unburnt fuel, caused by misfiring or excessively rich mixtures
CO=partially burnt fuel, usually an indicator of a too-rich mixture
NOx=excessive cylinder temperatures, usually from a too-lean mixture under load.

HC and CO being high point toward a rich air-fuel mixture. In this case, since there is not enough oxygen to support complete combustion, the reaction stops short at CO instead of CO2.

The air pump, if it's like my 560SEL, only operates on cold start before the O2 sensor starts working. The way the catalytic converter is set up on most modern cars is the reduction catalyst (for NOx) followed by the oxidation catalyst (for HC and CO). That way the O2 stripped off of NOx is available to oxidize HC and CO in the oxidation catalyst just downstream (or in the same shell). Also, it is necessary for the air-fuel mixture to go lean every now and then so the oxidation catalyst can operate when NOx is low (since a lean mixture will result in some O2 being present). That is the job of the O2 sensor, and if it does not switch and causes a rich mixture, the HC and CO will be high without the needed O2 in the exhaust. This will give the impression of a bad catalytic converter when in fact it just can't do its job. So, in your case, make sure the O2 sensor is operating as it should. If it is, then suspect a failed catalytic converter. If the O2 sensor is not operating, check the air-fuel adjustment at the air flow meter (refer to the shop manual for this). A rich mixture normally will not cause drivability problems or a significant loss of fuel economy unless it's ridiculously rich.

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Erich Loepke
2010 Ford Focus
Currently Benz-less