2024 Sierra 5.3 strange sounds

[EdTom]

Hi fellas, I’ve been meaning to post this and now that I’ve heard another strange sound tonight it’s time. I’ll try to be brief. I purchased a new Sierra 1500 with a 5.3 engine in March this year. First issue, on a cold start if I’m outside the cab near the engine I hear what sounds like popping noises (like popcorn popping). When the engine warms up it purrs like a kitten and sounds normal. Took it back to the dealership and they say nothings wrong with it. Second issue, the hissing sound when a door gets opened. I’ve been told it’s the fuel pump priming. Walked by the truck yesterday without a key and didn’t open a door and heard it. Have no clue what activated it? Didn’t even touch the vehicle. Third issue, when the truck is shut off within two minutes I hear what sounds like relay’s shutting off under the dashboard (fairly loudly). Fourth issue, heard what sounded like a faint activated smoke detector like sound coming from inside the engine compartment while the vehicle was parked in the garage (faint beep, beep). Truck was parked and engine turned off an hour prior to hearing that noise. It eventually stopped. I’ve purchased three new Tahoes with 5.3s in the past and have never encountered any of these sounds. I appreciate any feedback you knowledgeable guys have with this, thanks!
 

[DSW1519]

I don't have any experience with your 1st or 4th issues. On the 2nd and 3rd issues those are normal. Yes it's the fuel pump and relays shutting down. I experienced this with both my 2023 and my 2021 

[Silverado4x4]

10 hours ago, EdTom said:

Hi fellas, I’ve been meaning to post this and now that I’ve heard another strange sound tonight it’s time. I’ll try to be brief. I purchased a new Sierra 1500 with a 5.3 engine in March this year. First issue, on a cold start if I’m outside the cab near the engine I hear what sounds like popping noises (like popcorn popping). When the engine warms up it purrs like a kitten and sounds normal. Took it back to the dealership and they say nothings wrong with it. Second issue, the hissing sound when a door gets opened. I’ve been told it’s the fuel pump priming. Walked by the truck yesterday without a key and didn’t open a door and heard it. Have no clue what activated it? Didn’t even touch the vehicle. Third issue, when the truck is shut off within two minutes I hear what sounds like relay’s shutting off under the dashboard (fairly loudly). Fourth issue, heard what sounded like a faint activated smoke detector like sound coming from inside the engine compartment while the vehicle was parked in the garage (faint beep, beep). Truck was parked and engine turned off an hour prior to hearing that noise. It eventually stopped. I’ve purchased three new Tahoes with 5.3s in the past and have never encountered any of these sounds. I appreciate any feedback you knowledgeable guys have with this, thanks!
 

#1 that's something we would have to hear on a video, my 2019 makes a wishing noise about every 3 seconds on first start up then stops, done it since new.

 

#2 the hissing sound is the fuel pump priming it will do it when unlocking with fob or opening the door without fob only does it after truck sits for awhile. They all do it. 

 

#3 the clicking noises are computer's shutting down the relay’s for lack of better terms, they all do it.

Edited July 17, 2024 by Silverado4x4

[EdTom]

Received and reviewed your feedback on this, thank you

[newdude]

11 hours ago, EdTom said:

First issue, on a cold start if I’m outside the cab near the engine I hear what sounds like popping noises (like popcorn popping). When the engine warms up it purrs like a kitten and sounds normal. Took it back to the dealership and they say nothings wrong with it.

 

Second issue, the hissing sound when a door gets opened. I’ve been told it’s the fuel pump priming. Walked by the truck yesterday without a key and didn’t open a door and heard it. Have no clue what activated it? Didn’t even touch the vehicle.

 

Third issue, when the truck is shut off within two minutes I hear what sounds like relay’s shutting off under the dashboard (fairly loudly).

 

Fourth issue, heard what sounded like a faint activated smoke detector like sound coming from inside the engine compartment while the vehicle was parked in the garage (faint beep, beep). Truck was parked and engine turned off an hour prior to hearing that noise. It eventually stopped. 
 

 

 

1 - These engines double pulse the injectors and alter timing to heat the catalyst faster which can cause some audible cold start noises.  The other alternative is a lifter that isn't pumping with oil right away.  A video recording of a cold start would help determine this one better.  

 

2 - Normal.  Fuel pump prime.  Done this since 2017.

 

3 - Normal.  

 

4 - Normal.  

[EdTom]

Thanks for your response back bud. This truck looks and runs great. I’ll assume those unusual sounds are normal and I’ll disregard them. 

[rrmccabe]

My new 2024 LTZ has the same noises.  The first day I got it I was waiting for a cold can of coke to roll out of a slot somewhere.

[EdTom]

That’s actually a pretty damn accurate description