is there a way of telling when its on closed loop or not.

i can only assume mine isnt as i tried unplugging the lambda sensor and the idle didnt alter in anyway? and also its using as much fuel as the old map

one thing that can be said is its a testiment to stu's mapping skills as, if i havent been using the closed loop map (due to the sensor issues) the car has been idling much happier than the old stage 3 chip that used to be installed