Vehicle has twice failed to accelerate while driving in traffic. The vehicle had just had the tires balanced/rotated and an engine oil and filter change. Dealership Service Adviser and their Transmission specialist connected it to a computer and two fault errors indicated that the issue had happened on two separate occasions as reported. They noted that there seems to be some sort of transmission gearing and/or software issue. I refused to accept the vehicle. They agreed to keep and drive it to try and replicate the problem, that may never happen again? In the meantime those vehicle may be very deadly to all drivers/owners if they fail to accelerate the vehicle upon demand in traffic resulting in a possible vehicle accident/serious bodily injuries or death to the driver, passengers or additional drivers in surrounding vehicles.