Not to fault you for trying, but soaking them in carb cleaner is about as worthless as a screen door on a submarine. There are a few companies which will "attempt" to clean CIS injectors but will give no promisses to the success. They use ultronic cleaning baths in at least two different ways, some a third attempt is done if flow shows no real benefits from the first two attempts, and state if the injectors can't be made to improve then they must be replaced. The screen inside is the problem as the injectors are pressed together and you can not get to the fine screen inside. Some people have said they "backflushed" their injectors but this can't be done with CIS injectors, EFI injectors yes but not with CIS injectors. But even though you are trying, if you have no way to test the crack-open pressure and the flow output, you will never really know if you made any progress.I'm in the process of cleaning injectors and want to clean up the lines too. Whats the process to clean the inside of the lines?
I'm soaking the injectors in carb cleaner.
The lines could be brushed clean if you can find a brush small enough or by using a rifle cleaning kit if it will fit, and the bends straightened out. Other then that I would think doing an ultrasonic cleaning would be again the best way. You can buy small ultrasonic cleaning machines for about $50 or more, but they are small. The injectors would fit but I don't know about the lines?