Fuel pump runs steady

An electronic fuel pump is not designed to be on off on off.

It is designed to be on and provide a particular pressure in the line.

Think you electrical wiring in your home.
There is 120v ( pressure) in the wires to an outlet all the time, no problem.

Same with fuel pump it just runs and builds pressure till it reaches its max design pressure and just stays there till there is flow then the pressure will drop a bit, a well designed pump will have let's say 5 psi at 20 gpm ( just numbers I made up) and 5 psi at 0gpm.

A mechanical fuel pump does the same thing, as long as the cam is rotating the pump is pumping, at some point it will just hold the pressure even if no flow is happening, if you ran the engine off another fuel pump source but kept the mechanical pump hooked up to a dead ended tube with a guage the guage would not just continue to rise till it burst. It would top out at the pressure the pump was set to provide.


If you have excess pressure for your carb you need a regulator.