I have a 2006 M45 with 117k miles. I was having the issue where you can only fill the tank halfway, for about a week. All of a sudden, I could fill my tank all the way up. A few days after the issue went away, I got an SES light with OBD2 code p0442 - small EVAP system leak.
I read on here and, multiple other Infiniti forums, about the technical service bulletin where they put some kind of splash shield around something in the gas tank. My Infiniti dealership said that since I was able to fill the tank that they didn’t think the TSB applied to me. It turns out that they were right, and I hate to admit that.
I got on YouTube because it’s the best resource in the whole world, and looked up “Ratchets and Wrenches evap.” He’s one of my favorite YT’ers. Anyway, sure enough he had a video on what to do if your tank won’t fill up all the way. He attributed the issue to the normally-open charcoal tank vent valve. I took the tank vent valve out and used my Power Probe to apply 12v to the solenoid, which closed the valve, then put my vac tester on the outlet side, vac’d it down and it had a small leak. But that’s not all. After cycling it a few times, the normally-open valve stuck closed with no voltage being applied. With the vent valve sometimes staying stuck in the closed position, the pressure couldn’t escape the tank , so I couldn’t fill it all the way. The valve was also the source of the small evap system leak that set code p0442.
Anyway, the dealer isn’t always wrong. Whodathunkit?
Part number was Nissan 14935-JF01C