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Fuel Pressure Systems

What pressure does the common fuel tank mounted fuel pump maintain in a modern vehicle’s fuel system? What would be the flow rate of this? In the event of an accident, are there safeguards to stop the fuel pump from operating?

Don’t know the answers to 1 and 2, but YES, there is an inertia switch that will shut off current to the fuel pump in the event of a crash.

The owner’s manual should show you where this switch is located on your vehicle, and how to reset it.

I think the pressure ranges between systems from forty to seventy PSI. If there is no inertia switch, the pump stops when the engine stops turning. The sensors in the ignition system tell the computer to turn the pump off. It’s that or something like it.

Thank you.

Thank you

In addition to the inertia cut off switch, all systems will cut off the fuel pump if the engine stops turning.