what do i look for if my car is leaning out, what signs are shown, i couldnt find anything searching so i thought i would post on here and see who posts what....

when i race through all gears my A/F doesent show that the car is leaning out, but sometimes the engine sound differently, like in 4th, but i'm sure i'm not leaning out, meerly wanted to know what signs or symptoms are shown when a 7 is leaning....