I recently installed a Nismo FPR and a fuel pressure gauge. I've adjusted my pressure according to the specs (43 psi with ignition switched to 'ON', 36 psi at idle) but noticed after the car is shutdown the fuel pressure slowly bleads off until it reads almost zero. Is this normal? If not, I'm thinking a check valve in the fuel pump might have failed. Thanks, Steve '92 SE-R, VE powered