Please Help.

https://www.tacomaworld.com/threads/strange-noise-when-engine-shuts-off.254847/

 

sounds like emissions equipment; no idea if the noise is normal.

 

I heard a lot a bad things about those systems. Guess Ill get a 4.0 before 2012 as I am looking for an older vehicle

 

^The secondary air injection system is inherently unreliable because the components are exposed to dirty hot exhaust gases. If your state doesn't have yearly emissions checks with visual inspection, you can delete the system with a $500 Hewitt bypass kit: https://hewitt-tech.com/product/secondary-air-injection-system-bypass-kit-gen-2-plug-play/ In principle, it's akin to doing EGR delete on '90s vehicles.

 

That's the SAIS pump doing its EPA bullshit. Be worried when that sound stops happening. You'll hear it more when shutting down after shorts trips when the engine doesn't get up to temp and stay there for a bit.

It's 110% normal, stop freaking out.

Now go replace the air pump foam filter with a Uni style oiled filter pronto...

 

HPTuners lets you turn off all reporting of the SAIS to prevent setting codes. At least it use to.