I you have a newer Nissan H21/H25 you must drain the tar out of the regulator. The truck will seem to need a tune up, but it starving for fuel. There is also a small filter and oring in the fuel electronic lock off. There is also screen filter that should be cleaned, we use brake cleaner. Nissan suggestes replace this filter the first 200 hours, we are doing that and once a year.
If anyone needs help on a nisssan Parts or Service drop me a line.....

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