Hi Edward
That little screw adjustment selector, basically is a selection of 4 different Map , that you can select , by turning that selector with the screwdriver.
The map that you were using most probably was adjusted for a specific engine set up.
What you did , it went to a another program/map , with a basic program that came from a factory.
Normally , you will select different setups for different engines or fuels.
Hopefully that works for you
Juan
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