Help identifying noise from intake manifold

Have you diagnosed it?

 

Man, that is spot-on similar tone and nature of sound. I'll bet it is the intake mani gasket with OP just like it was with yours. Twice.

 

This is great thank you, I do want to replace the gasket between intake and throttle body when I do it so whenever I can get my hands on an OEM gasket I'll get on that.

 

I didn't replace mine. I was just very careful pulling the throttle body off. The gasket seemed quite durable, a mix of pliable plastic and rubber.

 

Okay then maybe I'll just get that out of the way today, its difficult to know if my initial job was thorough since it's still attached.

 

If you haven't checked this out yet, it's helpful...https://www.youtube.com/watch?v=HUG_4864ovU&t=848s&ab_channel=ToyotaMaintenance

 

This does sound very close to the noise I'm hearing, however mine is totally intermittent and only makes that sound at low rpms or idle. It also was always only starting after being driven for at least 20-30 minutes and then would continue from that point forward. I did drive the truck for that long yesterday and the noise still has not come back. I will probably just change the intake manifold gaskets anyways since just about all the gaskets on this thing are rotten and because it's not a super expensive or difficult fix. I think maybe when the engine would run a while, the rink of gunk around the butterfly flap would warm up and become softer so that when the flap was mostly closed it would seal along the sides like a bubble and pop open due to the vacuum. When I was poking around with the stethoscope I couldn't hear the pop coming from the intake manifold or from around the gaskets either. I just initially heard the sound coming from the intake manifold area.

 

Yeah, my intake manifold gasket is bad again.

 

You are quite possibly right on that. It's the one thing I'll say, it sounded like it was a larger orifice.

And those oiled filters are a huge cause of TB buildup. My truck has always seen OEM buildup. I have zero buildup after almost 80k miles of driving, and I haven't cleaned the TB once. All the more reason to get rid of that oiled filter STAT.