VW 98 Passat Igntion Lock 4

The key won't return to the run position when starting. You can physicaly turn it to run. The spring internally has either disconnected or broken. This is the second time. The last time was a typical $400 dealer repair. Is the spring mechanism in the lock cylinder or the lock housing? Replacing the cylinder is a do it your self job requiring no tools except a screwdriver and paper clip. The lock housing requires removal of the steering wheel and dealing with the air bag and best left to the pros. If anyone knows which piece has the spring mechanism that woiuld be helpful