The previous owner told me that at some point in the cars life, there was a fuel leak at "the fuel pressure regulator". So his mech replaced the "fuel pressure regulator" with this Bosch one for a BMW.
After I took possession of the car, I discovered that what was actually removed was one of two fuel dampers, not the actual FPR. The FPR is still in the car, and still original as far as I know. Here is a picture of an engine bay from the same year, same model Impulse as mine, the arrow points to the damper.
The car actually has two dampers, one on the input side and one on the output side of the fuel rail. If you look at the pic above, you can see the other one behind the arrow. You can also see the pressure regulator underneath the damper where the arrow points.
Your Piazza's from Oz do not have these dampers? I believe this is the correct info:
8944083700 198503 - 198705 + 4ZC1 ENG(LR9) DAMPER; FUEL
Now, I don't think this part is needed either, not to get the car running right, but I can't imagine it would hurt to have some of the missing factory parts replaced.
One thing that might be going on now, which is causing the fuel pressure to be high, is that I replaced tons of stuff under the hood, including my injectors. So now, I have new injectors that are squirting really well, and maybe the fuel pressure is just too high now with the new injectors, where before, the old injectors were a bit clogged and the fuel pressure was high, but working ok considering this. My plugs are black and the car spits and pops at me while running. I have a pressure gauge hooked up and the pressure is constant around 49-51 psi, which is too high.
So I think my buddy Mike is correct that I am getting too much fuel and I have to get it under control. I with there was another aftermarket pressure regulator that I could buy knowing it would work.
Bart
