08 mini turbo code 3091 intermittent

[dana_]

Hi all,

had a few issues , throttle body , coil packs, now last issue is start/stall and 100 psi live fuel pressure with p3091 code thrown. 75 psi fuel pressure measured into hpfp. replaced hpfp with ebay one.... same issue ... starts and stalls, sputters while I flutter the accelerator peddle and eventually .... runs great as live fuel pressure bounces up to 700psi.... finally. any ideas? someone suggested fuel rail pressure sensor but I don't think that would be it... ideas???
measure signal at solenoid on hpfp.... 3.5-4.8 volts, 4.8 when at 100 psi. modulating at 700 psi.


any help appreciated