Mix up some soapy water and pour or spray it onto the tire Keep reading for more information It'll bubble around the leak and tell you where it is
19 Facts About Fix-It Felix Jr. (Wreck-It Ralph) - Facts.net
Fix a flat is for emergencies only, and won't work for leaks outside of the tread, like on the sidewall, tire bead, or valve stem
Or just take it to a tire shop.
However, while this will serve as a temporary measure to avoid being stranded, many enthusiasts believe that it should not be used on rims This is because cleaning the solution, when dried on the rim, will become a big issue