hey just wondering when signs to look for if the fuel injector needs to be cleaned, or at what kms(miles)?

 

its not part of the regular matinance. basicly if you change your fuel filter when required and run good gas, you shouldnt have to clean your injectors.

 

You could always run a bottle of the injector cleaner through the gas periodically if your worried about it.
But to answer your question misfires would be one of the main symptoms.Caussed by a lean condition in the cylinder with the clogged injector.