I have a cauna 3 cylinder motor with 3 bing 54 carbs. The engine runs great. It idles a little ruff. When on approach to land when pulling the throttle back to idle it will studder and stall, only while decending to land and no other time. If I keep the rpms up over idle it will not happen but I have to have a longer approach as I am still with some thrust and slowing down becomes harder.
I have tried to give extra fuel for choke to test if it was too much fuel or not enough as the problem but no change. I have also tried to catch it by giving throttle but can not always catch it before stall.
What could be the problem. It could be 1 or 2 of the carbs doing it and not all three.