When I called the seller of the '90 300SE that I eventually bought, he wanted me to meet him at his house. He was at his work and was planning to drive straight home to show me the car and let me drive it.

About 5 minutes later, he called back and changed the viewing venue to a place about 5 miles away.

I later figured out that he probably changed the venue when he realized that he would be starting the car cold, with me there to drive it, and risked having to explain when the car was hanging in gear for the first half mile.

To this day, I do not know if he knew it (delays up-shift for emissions) was by design or if he was trying to pull a fast one on me.