What years did Ford diesels have a fuel injection rack problem?

What is your question?

Hi I live in Costa Rica and I am interested in buying a 2002 Ford Ranger xlt 4x4 turbo diesel. Someone told me Ford had a huge problem with the fuel injector "tray" or "rack". I am woman with no mechanical knowledge and would like to know someones opinion as to wether or not this may be a dependable vehicle. Thank you