Weird noise when starting 2006 4runner

[robdog09]

A few weeks ago, I started haring this noise for the first 15-20 seconds of the car running. I thought it was maybe something only when it was cold, but i can turn the car off, and back on, and it will go again. Its a high pitched mechanical hum, which all the sudden turns off around 20 seconds into the car running. It sounds like a vacuum of some sort.

It turns off in this video around 3-4 seconds in. Curious if anyone knows what this is, and if its a problem?

https://youtu.be/OpI3LgZd6aY

 

[AuSeeker]

Check your link, it says no video found.

 

[robdog09]

Apologies! Updated in orig post, and below:

https://youtu.be/OpI3LgZd6aY

 

[riceandpho]

could be alternator bearing. or other idle bearings.

 

[5vzT4R]

That would be your air injection pump, most likely on its way out. Google "4runner aip" and there is alot of information on it and how to fix it.

 

[AuSeeker]

A few weeks ago, I started haring this noise for the first 15-20 seconds of the car running. I thought it was maybe something only when it was cold, but i can turn the car off, and back on, and it will go again. Its a high pitched mechanical hum, which all the sudden turns off around 20 seconds into the car running. It sounds like a vacuum of some sort.

It turns off in this video around 3-4 seconds in. Curious if anyone knows what this is, and if its a problem?

https://youtu.be/OpI3LgZd6aY

What year model is your T4R V8?

That would be your air injection pump, most likely on its way out. Google "4runner aip" and there is alot of information on it and how to fix it.

Very possible that it's the AIP, if his is the correct year model, 2005 or later.

 

[simple]

There was a guy here who said he had what sounded like a shop vac in his engine compartment sometimes. He also started having serious issues with his car. Ended up being the alternator I think. Check out this thread.

http://www.toyota-4runner.org/4th-gen-t4rs/174030-secondary-air-injection-pump-failure-v8s-important-6.html