I think I already know the answer but how often should the regulator be open allowing fuel to return to the tank, particularly at idle? I'm doing some last minute maintenance before a trip and was double checking the hose clamps in the tank to make sure I didn't have a slight leak. I've noticed a bit of a hesitation and just wanted to verify there wasn't still an issue there. I had the fuel level sending unit out with the fuel level below the lowest hose clamp so I had a clear view. I noticed the fuel was rolling while running as fuel was being returned. I expect this to be relatively normal provided I have adequate fuel pressure to the rail. I know the proper thing to do is get a fuel pressure gauge and I might try and borrow one from the parts store tomorrow. I just thought I might save some time if it was odd to begin with.