My 2012 buick regal is pulsing when sitting idle at a stop sign or traffic light

What is your question?

The car just turned over 80K miles, and aside from keeping up on the oil changes and tire rotations, the only thing that has been replaced were a set of four new tires back in December.

What makes this problem better or worse?

The pulsing only happens when the car is sitting idle at a stop sign or traffic light.

How long has your 2012 Buick Regal had this problem?

7-10 days