[jontalk]

They replaced the sensor with a used one as a test to see if the code was thrown again with a different sensor. Since it was, it seemed logical that the problem doesn't seem to be sensor related but instead wiring or DME issues. This is why the next step was to update the software and in doing so, it throws a completely different code than ever before. FYI, the sensor ageing code was showing up regularly while the Cat Ageing only happened once a couple of years or more ago.

I've got the car on the market right now but in the meantime I'm keeping my fingers crossed. Even the very savvy technician says it's a rather odd problem since it's been inconsistent.