Air compressor noise while truck is parked???

Walked by my truck and heard the buzzing/humming sound. Grabbed the creeper and a flashlight and see this device that making the noise. Sounds exactly like a compressor, just very quiet. Pics are looking from the rear axle towards the front. I grabbed that part, and it was vibrating. While I was posting this, it stopped.

 

It’s part of the emissions system. It’s purging. No big whoop.

 

Here is a thread.

https://www.tacomaworld.com/threads/2018-noise-when-car-shuts-off.579499/#post-19223394

 

Y’all are awesome, thanks!

 

Mine never made any noise. Not sure I have that thing...

 

You do they all have it.

 

I’ve had mine for over a year and never heard it.

I got my wife a ‘17 Tahoe Premier. I hooked a trailer up to it one time, and I hear a compressor running. Turns out, it has air shocks and a compre to level the load. I had no idea.

 

First time I heard this I was camping in my topper in the middle of nowhere and woke up to it. Confused the hell out of me.

 

***
This is the only thingy I have in there. Looks different from the one posted by OP. Never made any noises.
Is my truck a LEMON? and should I part out?

 

Heard mine the first time just today.

 

Who the hell reads the manual

 

Special parameters need to be met before it'll go off. It pressurizes the tank to see if there's an evap leak.

 

Same, cept I was coming down off an acid trip w my wife. I had to reassure her it was normal, but in reality, I had no idea.

 

Wife's brand spanking new Mazda does the same thing but is MUCH louder.

 

It's the evaporative emmissions system leak detection pump. Damned emissions laws making my truck buzz... Fun fact: it's about $300 for the pump if you break it.

 

It’s actually in the manual that it will make noise after shutdown to purge

 

I'll just use the ARB twin.