The engine of your Mini Cooper needs regular maintenance. Rough engine idle could cause irreparable damages to the engine of your vehicle in the long run. So, factors responsible for such kinds of unusual behavior by the engine should be identified and repaired immediately. For more information in this regard, please go through this presentation.
15. A vacuum leak is a leak
between the engine and
the mass airflow sensor
which could cause an
immeasurable amount of
air to enter the combustion
chamber.
16. Presence of an excessive amount of air could
cause rough engine idle when cold.