O2 sensor will sit static at 0.44v at ecu if the system is running open loop. This means all values are defaulted, o2 levels and fueling map then runs rich just as if it was in auto choke during startup which is also open loop.
there are other factors e.g. if ur coolant sensor was stuck saying cold the car would stay open loop and never swap over to read o2 sensor values. You see what i mean. Check your other readings and only when the car is up to temp and ready will it swap over to closed loop values. Another reason is that it drives a heater in the o2 sensor to Heat it up so it can work correctly. If this relay or drivers doesn't work again it wont go closed loop so check heater values for voltage on startup of car and periodically after. Ive asked seperately for a list of things that impact open loop decision so i hope it helps if answered. All mems ecus perform in similar mannor for open closed loop so doesnt really matter if mems1.6 or mems3. Only real difference is if it uses a relay pack or drivers direct from ecu or bcu. Tnx.