3rd gen Tacoma on and off whirring noise

Hello, new to the forum and to Tacomas in general. I don’t even know how to describe the issue I’m having as I’ve never heard this sound in any of my other vehicles, maybe something is already out there in the forums. I have a 2021 Tacoma AC TRD Sport manual. It has developed a weird noise, I bought the truck at 27k miles and it started developing within the last 1000 miles (~32k). Every minute or two this whirring noise will come on and last for about 2-3 seconds and then shut off. It’s pretty consistent almost like a sensor is kicking something on and off, especially consistent when driving longer distances. It’s never at idle, always while driving and not specific to any speed or gear. No one I know that own 3rd Sometime a has heard it. Sometimes when the sound kicks on I’ll even feel my truck instantly slow down as if it’s starved of fuel for a few seconds and then when the sound turns off it’s business as usual. Not necessarily convinced it’s a fuel related issue but unsure. It’s driving me insane especially with only 33k miles on it, I’m not sure what it is. I went on a test drive with a Toyota tech and of course the sound didn’t come on and they weren’t much help. I grabbed a few videos, anyone know what it might be? Thanks for looking.

https://youtube.com/shorts/qyavDxD0g90?si=UCIobLPJtfo2YUG1

https://youtube.com/shorts/4aINf8iosNc?si=EC4fmWNWLF_GXEkP

 

Welcome. Normal. It's A/C whirl. My 2020 has done this from day one. My wife even thinks it endearing and thinks it adds to the character of the truck. Others have reported this too.

 

Interesting, thanks. Even when my AC is off??

 

Apparently AC will work in the background to keep the humidity down depending on the setting on your HVAC controls. I notice this noise more in the summer for sure as here in the PNW we don't use AC as much in the fall/winter/spring. It will help to defog in the those times tho.

However, I do believe there is a TSB that will address this. See attached. Requires that they tear your dash apart and replace your EVAP core. The noise is harmless and does not impact performance or has caused any known issues other than annoying to most.

I'm going to keep my dash in tact and just live with the intermittent noise.

 

Thanks @Canadian Caber. I’m in The PNW as well, don’t think I’ve even used my AC yet as I bought the truck mid September. But this makes sense, and after finding a few more forums with the same noise. I don’t want to mess with it and I’ll just live with it especially since it’s harmless.