I just bought my first Honda for my son. Fixer upper, turned out it needed a motor. F23a4 ULEV. I put in a low mileage JDM motor. New flywheel, clutch kit, timing belts, water pump, etc. Then no spark! After trying everything I gave up and brought it to a professional. After a month of trying everything (everything I tried) he tracked it down to a ground connection! The ground connection nearest the temperature sending unit apparently wasn't 100% clean so I had no spark!??? Really? Why?