I've got a B&M Commandflo FPR and a Bosch fuel pump that I've recently installed. I've noticed that whenever I shut the engine off, the fuel pressure gauge indicates 0 It would be difficult to start the engine unless I crank it several times to build fuel pressure. Once the engine is started it reads 32 psi and when I attempted to adjust the fuel pressure, it would not respond... I pulled the vacuum hose off the FPR but the fuel pressure remains constant, at 32 psi. I also pinched the fuel return line and again there is no change in fuel pressure. I've driven around for the past couple of days with this problem and doesn't seem to have an affect on drivability since I am not on boost yet.... any idea what the problem is?

Thanks

 

Is the pump an inline one? Is it between the filter and the rail? Is your fp gauge on your filter? If so, you're not going to get accurate reasings.

 

I found the problem.... a rubber hose that I used to connect the pump to the fuel pump lid assembly split in a big way. I replaced the culprit with high pressure fuel line and it works fine again.