Dear,
I am experiencing same problem along with way to vibration on stop with AC on and Tranny on D (Drive).
After long research, reading blogs and forums and watching videos on same issues, I found that Lancer has a generic issue of IAC valve [Idle Air Control] (also know as stepping motor/RPM control/Air Valve/IAC Sensor/Air Sensor) getting faulty. A picture for your reference:

May be following answer by some Gora will help you understand better.

By the way, you can first go with cleaning the IAC valve but its recommended to change the bloody thing.
You can get it from
Dewan @ 4-8k new
Car Market @ 2.5k used (like Shershah and Bilal Ganj)
Ali Express @ 2k new (chines replica)
I have ordered mine from Ali Express and currently waiting for it desperately.