Odd rumbling noise after shut off

Upload the vid to utube and then post the "share" link in a post here.

The noise is at the 17 and 38 second marks.

Check up front and see if it's the grill shutters struggling to open/close. You have a set in the grill, and another set in front of the Intercooler down below.

You also have a vacuum reservoir on the firewall that is connected to lots of things and if it is bleeding down, it might be something moving as a result.

Then finally, it's not impossible for one or more of the HVAC damper-doors to move and create a sound that is muffeled like in a deep box.

These trucks have quite the ensemble of systems and subsystems running off a bunch of computers and solenoids and electric motors. It's crazy

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Did you find out the reason of your truck rumbling? Mine does it and will run the battery down if not drove regularly. I have plans to take mine to the dealer under warranty but I wanted to have an idea to tell them.

KAV45 said:

New to the forum...I have a 2018 F150 with the 3.5 ecoboost with roughly 42k miles. It's been extremely cold here in the midwest and my truck has recently started making this rumbling noise and can't seem to find any similar noises searching the webs. Thought maybe someone here could help me out. It happens about 5 times after shut off no matter if it's cold or warm about 20-30 seconds part. It also happens sometimes if it's been setting and I just open the door. I have a video but not sure how to upload. Thanks for the help!

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I have the same noise. Going to get it checked.

Curious if anyone has an update on this noise. My husband's truck has been doing this for some time. Had it in for an oil change at the Ford dealer recently, and they had us schedule another appt to have this sound checked out. Appt isn't for another few weeks. Battery was tested on Feb 4th by dealer and battery good at that time. Husband went to start his truck this morning and wouldn't turn on. I believe whatever is causing this noise has probably finally killed the battery.

Anyone? I'm having this same issue.

I agree with snakebitten, it sounds like your grill shutters; I definitely hear a more "electric motor" type of sound from the second occurrence in the video. Have you tried popping the hood open before shutting down and listening for the noise?

I finally found a thread pertaining to this exact problem that gave me enough confidence to accept this sound as flawed as it seems (to me). It is the fuel pump continuously priming itself and readying for start.

In other words, I can no longer enjoy long breaks in my truck browsing the internet without either learning to accept the sound or placing the key fob 20+ feet away from the vehicle. I've also realized that even with the key fob away from the truck I cannot sit with the door ajar with out triggering the relentless fuel pump prime. We shall see what the future holds for my battery and the systems involving this repeated prime.

I suppose most people park and get out of their vehicle or idle. You really have to sit quietly for a few minutes after the vehicle is off to notice the sounds. Not even my Ford dealership could tell me what the sounds were after hearing them..... Thank you Ford forums.

I don't think your fuel pump should be running continuously. It should "prime" as you say, and then shut off as the pressure switch meets it's expectation.

At least many vehicles are setup like that oem.

It cycles for 3 seconds every 10-40 seconds until the fob is 20 feet away and the door is closed. I have an appointment with Ford tomorrow to take a look. It'll be piece of mind at the least. Thanks for your input.

Ahhhh
Makes more sense.
I thought it was running continuously.

Good luck

oregonred81 said:

It cycles for 3 seconds every 10-40 seconds until the fob is 20 feet away and the door is closed. I have an appointment with Ford tomorrow to take a look. It'll be piece of mind at the least. Thanks for your input.

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snakebitten said:

I don't think your fuel pump should be running continuously. It should "prime" as you say, and then shut off as the pressure switch meets it's expectation.

At least many vehicles are setup like that oem.

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curious what you find out… as snake mentioned. Once the system reaches adequate pressure, the pump should not run. Could be a leak causing pressure drop, bad pressure sensor (but then you’d hopefully also see a code or have driveability issues.)

do all the proximity keys trigger the same “key on” functions? Im not too well versed in that aspect having the old fashioned insert-and-twist setup

something is telling the truck to do this. Gremlins such as this can be good at hiding out and throwing counter-intelligence at you

I have that same exact noise! Dropped it off at the dealer 3 different times for 4 days and they couldn’t get it to replicate. Anyone find a fix? I am thinking it’s something in my house? Like wifi interference? But that might be far fetched

Could it be a bad check valve in the pump allowing pressure to drop and then have to reprime?