Add FICHT Core Assembly replacement to rebuilding service. Some cores are so worn out that we can’t do anything with them. This part replacement requires a rebuild fee to accompany the core replacement. Please note that this FICHT Core Assembly is not a core charge, like from an auto parts store where you are charged for a part you must later return for refund. This core assembly is the center core of the injector and contains the moving parts that make up the injector.