The tech was probably talking about the stc(snap to connect) fitting on the back of the hpop. This is a very common failure and there have been two different updates to the fitting. The newest fitting is just a solid block instead of a stc style fitting. If its not that leaking the ipr may not be closing, leak at the top of the injectors, or case to head tubes. Also when you test with air you have to energize the ipr so it closes or all the air will just bypass it and it sounds like a leak. sorry for the long post.