Did they do it right?
Dealer adjusted throttle linkage. At a stop light the car idles at 550 RPM, but in Park, it can idle "fast" at 750 RPM. This is an improvement over the "fast' idle of 950 RPM - at that speed the engine would "wobble" the car.
Q: Should the "fast" idle be 550 RPM, or is 750 RPM okay?