Do these 02 Sensor readings from obd1 look correct?

Question

I have an issue at MOT test where I get high CO readings. I've triple checked the following:

Exhaust leaks
New downpipe
Air/Vacuum leaks
Compression
MULTEC electronic Carb new idling control stepper
Injector test
Plugs/leads/coil/distributor/rotor arm all brand new OEM parts
Check/cleaned breather system

I'm now going down the route of diagnostics with a borrowed opel scanner. The vehicle is a UK Vauxhall Cavalier or Opel Vectra A in European markets. We are dealing with OBD1 here as the car is 94 model.
What I'm seeing with the 02 sensor, and the resultant air/fuel ratio is a pulse but the pulse looks a bit jaggy in parts, and also the cycle doesn't seem equal. All the tests were done with the vehicle stationary.

Note the AF ratio is taken at a different time frame than the 02 sensor.
Can anyone with experience in reading these sensors tell if this look normal or not?
Edit - attach print out data at operating temp.

Thanks
Andrew
Edit:
I've now changed 02 sensor and things seem a lot better driveability wise and also looking at the traces for 02 and AF ratio. As shown below in before and after shots:

GdD · Answer

It's very hard to tell if the sensor figures are correct. O2 sensors become 'lazy' over time, with slower responses to changes in oxygen levels, this could explain the lagginess of the readings. O2 sensors can also become less accurate with age, and high CO is one possible result of that. So the sensors could be reading correctly part of the time, or they could be off, there's no way to know for sure. The high CO reading is an indication that something is wrong, and the O2 sensor is certainly one of the prime suspects for that, but there are other possibilities.
High CO is caused by a rich condition, which could also be caused by restricted airflow, faulty engine temperature sensor, faulty MAF/MAP sensor, or a problem in the throttle position sensor. If you know your O2 sensors are old it makes sense to replace them (presuming you have a post cat sensor as well, otherwise it's just the one), this may clear up your issue, or at least improve it. You could also look at engine temperature readings, air flow readings, presuming they are available, and see if they make sense.

Do these 02 Sensor readings from obd1 look correct?

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