I have a 93 Infiniti J30 and I was wondering if my fuel regulator is good. It has a small opening for vacuum which I can’t suck or blow through. It has two openings for fuel, top and bottom. I can blow through the top one and it comes out the bottom, but its better when I blow through the bottom and it comes out the top. In your opinion is this ok? I’m not sure. I’m replacing my filter and was wondering if I should replace this as well.
A fuel pressure regulator can only fail in a couple of ways. One is leakage through the diaphragm. If it holds a vacuum then the diaphragm is good. The other would be if it’s sticking and this would require a fuel pressure gauge to verify as the fuel pressure will change a little depending on manifold vacuum.
It’s unlikely that either of these things would cause a no-start condition.