There should be no reason to replace the injectors themselves if the engine was running up to snuff. Replacing all the injector o-rings should get things back to normal.
The International DT and T series HEUI engines will do the same thing when o-rings fail. It wasn't a real common problem, but it happens as the engine ages and the o-rings get hard and brittle.
Although the injectors are different from Int'l and Cat, the system operation is nearly identical.
Rex