Hello everyone, I have a 2002 F350 7.3 automatic 2wd dually Cab and chassis, Starts right up everytime but has bad miss to it. Hooked up a Modis scanner to it, no codes, went to running data screen and its telling me I have 5..yes 5 PSI fuel pressure at idle. Slowly raising RPMs to 1800 and getting 46-48 PSI, miss disappears. I took the FPR spring out and it is a factory (not blue) spring. Noticed there is a hole in center of valve mechanism?? Are the injector o-rings leaking? Why does the fuel pump only build pressure off idle?? I believe the truck should have 50+/- PSI at idle. Any help would be greatly appreciated Thanks

 

It's an electric fuel pump... so it makes no sense that pressure would rise with RPMs. A Modis scanner has a fuel pressure sensor that threads into the system? If not, it's unclear what you were reading because there is no fuel pressure sensor on the engine.

Maybe the last link in my signature will help you out.