72 Dart Struggles and Dies today, Why?

egr = exhaust gas recirculation valve. If your 72 has one. Drivers side of intake manifold. Single vacuum line attached. You should be able to get a finger or two in the diaphram from underneath , push up and open the valve by hand. If it doesn't still have the vacuum line attached, forget it. It can't open and get stuck on its on.
72 model factory service manual is a free download here somewhere. I dont have the link.