There`s alot of different ideas floating around these days, although bear in mind that if you have concerns about your fuel injectors operating perfectly, 2 maintenance approaches I have taken are (1) STP fuel injetor cleaner on last tank prior to oil change and (2) Lucas UCL/injector cleaner to improve fuel economy and somewhat quiet the engine.
However, these days, a spare set of new injectors can be purchased for as little as $100 in order to facilitate removal and testing or ultrasonic cleaning of the original ones. You can buy nozzle adapter with 12V harness for as little as $10 which allows you to spray the removed injectors out with brake cleaner while manually pulsating them with brake cleaner to test for leaks and spray patterns.
But, before going through all of the latter, it is helpful to know what type of issues that you are seeing, so as not to routinely add snake oils to mask a mechanical problem that may not be detectable by the onboard diagnotics (for example, excessive lash caused by damaged rockers and pushrods)
However, these days, a spare set of new injectors can be purchased for as little as $100 in order to facilitate removal and testing or ultrasonic cleaning of the original ones. You can buy nozzle adapter with 12V harness for as little as $10 which allows you to spray the removed injectors out with brake cleaner while manually pulsating them with brake cleaner to test for leaks and spray patterns.
But, before going through all of the latter, it is helpful to know what type of issues that you are seeing, so as not to routinely add snake oils to mask a mechanical problem that may not be detectable by the onboard diagnotics (for example, excessive lash caused by damaged rockers and pushrods)