Can you get access to details of the ecu data management?
I have a Rover Gems Plus8. The system monitors exhaust and has two O2 sensors for each cat. Upstream and downstream
Basically The upstream measures emissions and downstream post cat to indicate cat performance/ failure. It has heated sensors and monitors the heating too. I did have a post cat heater fault trigger the MIL but cleaning contacts sorted it. I have an Autel Maxiscan OBD unit that can delete minor detected faults and also check running data. It covers O2 sensors amongst the many other parameters.
Some systems can be “fooled” to compensate, I think a lot of the plug in chip devices do this by modifying signals.
There should be some aero experts who can-advise.
One point to watch is MOT. If you remove a cat then it is an auto fail just from a visual. Maybe a cat divert would be better? Some cars have that as a standard. Putting the car into a spirts mode triggers a divert valve or similar.
