When it comes to your car’s fuel injectors, replacement is something you shouldn’t have to worry about until well after 100,000 miles. Unless fuel that is seriously contaminated is used or the injector(s) suffer an electrical failure. Even though fuel injectors are highly precise engine components, they are also quite well built and designed to outlast most engines with normal maintenance. If low quality fuels, or contaminated fuels were used on a regular basis, this can degrade the injectors and cause premature failure. Also, lack of proper maintenance such as regular cleaning, can also lead to premature injector failure.
For more info, see Turbo Engine Parts Tips