Testing Fuel Pump pressure problem

[TSiRocker]

This morning I did the external BOSCH fuel pump test using the fuel pump test connector on the firewall. When I connect the wire to the battery, my fuel pressure gauge is reading is at 27psi, which seem to be normal, but the abnormal thing is that when I disconnect the wire to the connector, my fuel gauge reading drops to zero quite gradually.

Shouldn't it sustain the pressure for at least an hour or so?

 

[steve]

If the engine isn't running your fuel pressure should be reading the base numbers.
How long it takes for te pressure to bleed down depends on if you have an aftermarket FPR and how well the pump seals in the pickup tube.

Getting 27 psi using the test connector doesn't sound good.

Steve