Fuel Injectors

Car sat for a week and when I started it up it kind of chugged but started up. Half way down the block my check engine light came on. Took it to a local shop and was told that a fuel injector #3 error code was the cause of the check engine light. They cleared the light and told me that I should service the fuel injectors and replace the fuel filter. The car is running fine so should I ignore this for now? If not, can I service the injectors myself and replace the fuel filers? Thanks…Terry