you may have one or some leaky injector(s). When you turn off the engine
the leaky injector(s) drip, drip, drip thus give the cylinder(s) an extra
amount of fuel. The feeling of flooded engine is from there... If you let
it sit for a long period (over night) the extra amount of fuel is already
evaporated that's why you don't have the same problem at cold start up.