my first question to you about cleaning the injector assy and throttle body is "what did you use to clean it with?"
Using the wrong cleaner can damage parts internally and cause all sorts of problems.
Absolute 'no no's' are carb cleaner and brake cleaner, those cleaners are way too caustic and will eat up the rubber & plastic parts inside the injector body housing.
I use either an electric motor cleaner or a mild parts solvent and then blow dry with compressed air.