most likely are debris in the needle/seat or a leaking accel pump seal. Do you notice overly rich symptoms at full rich? Do you know where the fuel is leaking from specifically on the carb? Leak is likely occurring all the time, not just on shut down.
N64LR - RV-6A / IO-320, Flying as of 8/2015
N11LR - RV-10, Flying as of 12/2019