My fuel pressure gauge hose is just long enough to feed up to the window and close the hood. That said, you should definitely not see a 5-# drop from a throttle stab in neutral. In my second video I'm doing redline punch to get less than 1psi drop. Any less throttle and it didn't drop 1/2 psi.

I would take apart the FPR and check those two o-ring though i think just the inner one matters. I think the outer one goes to atmosphere. (So would come out to ground)

Somewhere i have a picture showing the size it's like 8mm OD 4mm id but that's mostly guessing.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)