EGR control valve. It lets vacuum through to the EGR valve (correctly identified) if the pressure in the exhaust (very small pressure) is sufficient enough to let the vacuum through to the EGR valve and open that. All that can only happen after the temperature controllled vacuum port ahead of the EGR control valve is open (engine warmed up).
With the pipe broken off (seen that too) you will have a permanent vacuum leak which will cause the engine to run rich. Just suck on the vacuum line that comes from the temperature controlled port (at the end of the air bypass valve) and goes to the top of the control valve on the temp.port end and you'll notice you can easily suck a lot of air there (which you should not be able to with engine running).
Enno
The cold start valve is further forward on the intake just behind the TB. It is as ENNO described, although I removed all of that stuff after I broke the EGR tube that goes into the exhaust manifold, when trying to loosen the nuts.
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