What is the difference between CFE Plus and CFE Plus WiFi?
CFE Plus WiFi hardware differs from the CFE Plus.
Therefore a CFE Plus cannot be upgraded to a CFE Plus Wifi.
The CFE Plus WiFi has a WiFi chip on board so the CFE Plus ECU can be used in several ways trough WiFi. (For example for displaying real time data on a smartphone from engine, reading DTC's).
You cannot 'upgrade' a CFE Plus to a CFE Plus WiFi with software or firmware.