Originally Posted by NYCGP
Car notices it is idling too low and stutters in an attempt to raise the RPMs. I actually had the car stall on me once. Car needs a certain amount of RPMs to maintain a healthy idle. In our cars (and most bimmers) it is between 600-700. If it didn't matter we would idle lower to reduce fuel consumption. Had a similar problem with the N54.
We keep idle 100% stock with our software. It might be slightly different right after you flash before it has time to adapt but under normal conditions should be the same as stock.