It's a fuel return based system. No pressure till that pump turns on

 

Wanting to depressurize my fuel line.

Why? to replace the fuel filter? I've found it not necessary to depressurize for that, just have a rag handy and wear eye protection.

 

yes to replace the fuel filter

 

Exactly what @Cusser suggested. If you've ever had a house, it's the same when working on the plumbing. Once you turn off/close the water meter valve, the only water you'll have is what's left over in the house. So on the vehicle, just be aware that some fuel will come out. latex gloves, eye protection and a couple rags is all you need.

 

Thanks

 

I didn't like the way Nissan designed the protective mount for the fuel filter on my 4-cylinder Frontier (don't know if VG33 fuel filter is different). So I re-engineered it.