1994 Nissan Maxima fuel injection tubes

RDURLACH

MEMBER
1994 NISSAN MAXIMA
6 CYL
2WD
AUTOMATIC
159,000 MILES

I have the VG30E engine. Three of the fuel injectors were bad (by resistance measurement). I am replacing all six while I'm in there.
I have removed the fuel delivery tubes that hold the injectors. The injector sockets or holders for cylinders 1, 3, and 5 (firewall side of engine) are clean and shiny inside. The other three, for cylinders 2, 4, and 6 (radiator side) have a fine uniform even deposit all over inside that gives the appearance of a matte finish, but is actually a deposit of some kind.

If I am not mistaken, the fuel flows through in the order 6, 4, 2, 1, 3, 5 with the pressure regulator at the end of the line which surprised me. I expected the fuel pressure regulator at the entrance to the fuel tube.

What could have caused such a uniform deposit inside 2, 4, and 6 and still leave not a trace inside 1, 3, and 5?

Should I replace the pressure regulator as a routine maintenance item?

Thank you,
Richard

p.S: It would be a challenge to photograph inside the injector sockets, but I could provide photos if it would help.

1 Reply

MHPAUTOS

MECHANIC
31,938 POSTS

Hi there,

Thank you for the donation,

I have not seen this first hand before, I can only think that there was some form of lubricant or anti seize used on these 3 injectors as normally they are clean, a pic would be interesting to see, but I feel that there is no real problem here, just clean the injector orifices and use a bit of vas on the seals so they don't bind when fitted, the regulator will not have to be replaced.

Mark (mhpautos)