Electric Fuel Pump Diode

[LT1B-Body]

So, I picked up an electric fuel pump controller, which I'm happy with so far.
In the instructions, it says to (optionally) put a diode (included) from the pos wire to ground, or across the pump wires.

Why is this? I've been reading a bunch, and I can't find a solid answer why this is a thing?

 

[ELCAM]

https://www.arrow.com/en/research-and-events/articles/flyback-protection-diodes

 

[WAGOOON]

A diode is a noise suppression device. It’s not gonna do much on a fuel pump.
Typically a diode would go on something like a fan relay. When the relay shuts off it sends a fly back pulse through the control wires that can really mess with ECM signals like the crank signal. Makes the engine lose synchronization. A diode absorbs that fly back pulse and eliminates it. You’ll also find diodes on A/C compressor clutches for the same reason.

 

[WAGOOON]

I guess maybe if the fuel pump is messing with your stereo system adding a humming noise to your speakers then maybe a diode might help to quiet that down I’m not really sure.

 

[Ernest]

I remember back in my early RC days(90s)... the brushed motors, at the time, that were used to power the wheels had a small disc capacitor across the positive and negative terminals.

But electrical motors with a flyback diode is new to me, they are typically used across the power activation terminals on switching relays to suppress/eliminate the high volage spike that was produced that typically destroy the internal contacts when the power was cut off.