Build your own Adjustable Electronic DC Load using Arduino

I built two of these boards now and they both react the same way . The current dooes not start reading until my load reaches 1700ma and it only reads .11amps any lower load and the current draw is 0.00. The schetch compiles and loads fine but the hardware does not work properly. changed both the mcp4921 and the opamp. No affect. Anyone have an idea what might be going on

suspect it might be the program, but a little week in that department. Help!