Buzzing Noise on Startup

Hey Guys,

I've been having a weird buzzing noise on startup when it's cold out. The noise seems to be coming from the pass side rear seat area. If I shut off the engine and restart, it doesn't come back.
Anyone have any idea what it might be? I was thinking evap system maybe?

Thanks

Bruce

 

Anyone?

 

Could it be your secondary air injection pumps? They are on the passenger side but under the hood. They come on for a very short time on cold start and then turn off.

 

Have you pulled to HVAC blower motor, there may be a piece of debris in there. It’s only 3 screws. It could also be one of the bearings in it going bad. It’s a common problem with most Toyota’s. If you have to get a replacement, stay away from the Dorman brand unless you want to replace it every 6 months

 

Danny3737- I replaced the blower motor last fall (OEM), that isn't it. I'm guessing it's the air injection pumps like G Man said. It's driving me crazy, having to restart it every morning to make the noise go away.