E28 535is Fuel Pressure

["Humke, Brian (GEAE)" <Brian.Humke@xxxxxxxxx>]

Hi,

Does anybody know what an acceptable residual fuel pressure is when the car
sits a few hours/overnight? I'm trying to track down a warm day/warm engine
long crank problem. 

My fuel pressure tests check okay per bentley i think...41 psi at idle, 47
psi when relay jumpered/car off.  Vacuum test seems ok too.

However, when I shut the car off, the pressure immediately drops to about
20psi...which seems resonable.  But, after a couple hours the pressure is
near zero (Bentley says the fuel system retains a "slight" pressure when car
is off).  I would think if i don't have any check valve/hose leaks the
pressure should hang around 20psi...the level when the car is first shut
off.  Comments?

Thanks,
Brian

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