DP Diaphragm and VTV Confusion

[caballo]

I noticed that my DP Diaphragm is missing a hose. I know its suppose to connect to the VTV, but i cant find any damn nipple to attach it to.

After studying this diagram, http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=EC&P=3 I realized that the end of the VTV doesn't lead anywhere. It only accepts one hose that leads from the DP Diaphragm and then it sucks air in from the little air filter? So my question is why is there a hose coming from the bottom of my VTV? Here is an above picture of the VTV

and the hose that comes from the bottom of the VTV

I have no idea where that hose leads.

Is my VTV installed upside down? Or do i grab that hose and attach it to the DT Diaphragm ? Or am totally wrong and took a picture of what I thought was a VTV, but ended up being some other component?

 

[metaphysico]

The first pic is a pic of the power valve (sorry dont know what toyota calls them). Its a throttle plate inside of the engine. The vtv (I believe called the vacuum translating valve) connects to the dp (dash pot) which touches the butterfly on the throttle body. It has just a short hose on it that connects between the vtv and the dp. Its job is to let the throttle close slowly, there is a small hole in the vtv basically that only lets it take in or release air at a slow rate. It keeps the throttle from snapping shut fast. I am guessing it helps slow the throttle closing so that the iac has time to work. The little air filter on it is where it takes in air and releases air. Takes in air when throttle is open and releases it slowly when throttle closes.

 

[CyFi6]

Physico got it pretty good, one thing to add though is that it is an emissions device. It helps reduce a high amount of HC's from entering the exhaust upon snapping the throttle closed.

 

[jetjock]

Yep, that's a pretty good description of what's involved here. The VTV allows air to flow freely into the dashpot as the throttle is opened but restricts flow outwards as the throttle is closed.

As Cy said the dashpot is an emissions device. It's purpose is to prevent a spike of HC when the throttle is abruptly closed. By slightly delaying the closure air is allowed in to complete the burning of fuel already metered (and therefore injected) by the AFM. The little filter on it keeps crap out of the valve when it's "inhaling".

Since the VTV is directional it needs to be installed in the correct orientation. See the TSRM for details.