s14 gtst

I just bought a walbro 255 lph fuel pump for my r33 rb25 powered s14 and now my car is running funny. The engine seems like it is hestiating when I boost above 0 psi. My A/F gauge says that it is running rich, which i expected. Also, when I cut the car off I can hear a sucking noise. I thought it was because I didn't have a full tank, but I just filled it up and I still have the same problem. If anyone has any clue to what the problem could be or if you have the installation instructions for the 240sx, I would appreciate it if you could post it. Or email me at dan_lee10210@yahoo.com... thanks

s14 gtst

I was also wondering if the stock KA fuel pump was bigger than a walbro 255 fuel pump. Because my walbro is smaller.

jonpowell

Buy an adjustable fuel pressure regulator and gauge. Set BASE fuel pressure to 43PSI and whatever it goes to once vacuum is applied is perfect. That should repair the richness problem.