CM2350 Code 4727

[Dieseltechjon]

I have the thing apart right now. As soon as its back together I run the injector leakage. I was looking at the fuel system schematic and for some reason it looks like the feed and return are tied together via that vent port, and this is before it reaches the fuel actuator inside the actuator housing. I know I can blow air through it but not sure what's acceptable. The actuator housing I have is a little different as well. It has what looks like a threaded insert in the cavity where the orifice is. It doesn't have a head on it either.