rb25det runs poorly
rb25det runs poorly
I'm putting an rb25det out of a wrecked '97 R33 skyline in my 240Z. The problem I'm having is the engine runs rough and very rich. The computer is shooting no codes, i tested the AFM, water temp switch, o2 sensor, and throttle position switch and they all seem ok. The fuel pressure is around 52 psi which seems a little high to me, I'm not sure what stock pressure is suppose to be. I have an aeromotive fuel pump that is suppose to be good for systems between 30-65 psi. I checked all the grounds I could find and they were good. I pulled the plugs and other than being a little carboned up which I expected they looked good. I made sure all 6 plugs were firing properly and reinstalled them. One thing i thought was strange the plugs were autolites, which i wouldnt expect to find in a japan only car. Just to confirm a fuel problem and not ignition i squeezed off the fuel line with some pliers (hack i know) and could get the engine to run much better by regulating fuel flow this way. Im not sure if the injectors are stock, or how to test that they are working properly. Sorry for the long post, but i wanted to cover everything i tried. Any help with this would be greatly appreciated.
you pretty much nailed it. your on the right track here, you have figured out the fuel pressure is to high, on most nissans with a return system the fuel pressure is around 36psi. You cut some of the fuel supply and your car started to run better. I have zero skyline experiance but I would say you got a problem with fuel supply or something going on with the return side causing blockage ie pinched return line or FP regulator is blocking the return.