Bmw b58 Rail Pressure drops engine off


New Member
Jul 11, 2023
Hi i have a 2018 bmw 540i with 148tkm
Car is on stage 2 Mgflasher ots map, car runs drives perfect no symptoms. I just read on forums to check railpressure every now and then. I checked warm engine Idle its 10map after engine shut off goes up 11 max then after 1 min it starts dropping, then after few min went down to 8 and I didn’t Observed more but i guess because off the pace that it felt, it would go down to zero maybe..

I checked my sparks next day 5pm , all sparks looks identical not a single one off them have fuel smell, or anything weird!

Is it Fuel injector leak?
Is it Hpfp valve?
My Logs Look good Afr, timing, fuel etc
Any help is appreciated thx in advance