Briggs 16.5 hp runs only on full choke. I cleaned the carb can it be the electric fuel regulator on the bottom of the carb?

dont believe its called a electric fuel regulator more of fuel shut off it just raises the float to off position, if you have a fuel pump and no power to the efr as you call it enough fuel can pass through to keep engine running but only on choke

take it out put finger over hole run engine and that will tell you