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What is this Electric pump noise? Accessory power alone - 2013 Mustang Boss 302

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Hey all,

What is this pump noise? (2013 Mustang Boss 302)

We had a new rear view mirror with LCD backup camera installed today and now there is a strange electric pump noise when you turn the accessory power on before you even start the car.

Any suggestions what the problem noise is related to

Did the installers tap into the wrong power lines or something?

Is it a coincidence that we have low fuel? (and maybe this is the first time we've heard this noise before?)

Anyone Anyone? Thanks! (need to know what to troubleshoot tomorrow exactly)

Here it is:

2012-Boss said:
It is normal. It is the electric fuel pump pressurizing the system. All of our cars do that.

Thanks are you sure sure? This is my roommates car, and I had the new backup camera installed as a gift today. He says he's never heard the sound before and is worried something is wrong.

Is it because he's listening for something to be wrong since we changed something? I want to be 100% sure this is normal and is supposed to happen (make the pump noise) every time.
Just found this:
(doesn't this mean it's supposed to be quiet if working normal?)

"Electric fuel pumps sometimes give you a warning that there is something wrong. A good running fuel pump is rarely heard. However, a plugged or restricted fuel filt"er will cause the pump to make a hum or whining noise when the key is turned on. You can turn the key to the run position without starting the car and if you can here the fuel pump then you can tell it is running.

The way to troubleshoot this condition is simple. First, turn the key to the “run” position but don’t start the engine, if you can hear the pump running quietly, it is probably ok. However, if the pump is loud, there is a chance that the fuel filter is restricted or the pump is getting tired.
Finally if you do not hear the fuel pump run at all, the pump is bad or the fuel pump relay is bad. Always check the relay first. You can jump the power to ground at the relay block to activate the fuel pump. If it runs the pump is fine and the relay is bad. Finally, if the fuel pump doesn’t run, the pump is bad and should be replaced along with the relay.

If in fact the fuel pump does require replacement, most mechanically inclined persons can replace mechanical and electric in-line fuel pumps in their driveway. However, replacing electric fuel pumps located in the fuel tank is a more daunting task. You will be required to drain the fuel tank and uninstall it from the vehicle. This is because the pump is in the top of the tank between the tank and the floor board. Some German and Asian vehicles allow you to access the fuel pump through a hatch in the floor board. To save time, money, and frustration it may be best to take your vehicle to a professional as they have all the right equipment and tools to perform the task safely and efficiently."
I just filled the tank up with gas, no change pump still engages in a loud way.

Is it really supposed to be this loud normal? (or is it wearing out, or an electrical current/draw mismatch?
2012-Boss said:
Unfortunately, I cannot tell from the video if it is abnormally loud. They are usually pretty easy to hear.

Here's the raw video, let me know if that helps.

I can hear it plenty loud on my computer. You'll hear it at the following spots. We are turning the key from Off, to Accessory On. (back and forth)
Mine always makes that sound too. It is only on startup. I bet the article is really saying that you should not hear it when the car is running, not for that 1 second. My 2011 GT made the same noise, same time.
Thanks guys that's what I was looking for, several people confirming that fuel pump noise level and timing is normal.
Thanks guys,

I just drove it to Serramonte Ford and the service guy says it's totally normal.

I think it was just something that went unnoticed until now. (Perfect storm brain game)

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