I am seeing 4.8V in my datalog

The voltage it is sending is the module trying to tell us that there is an error with the ethanol content sensor and that the compensation is out of range.  This will typically mean that there is some sort of chemical contaminant in the fuel and sends the sensor out of it's working range.  If possible you should drain the fuel from the car and flush the system with known good fuel and see if the issue returns.  If it does come back there was likely irreparable damage caused to the sensor and you will need to get a new one.

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