Cruise Control problems of the 2014 Infiniti QX60

This vehicle is equipped with intelligent cruise control. A test drive with the dealership on 11/19/2014 revealed, setting the cruise at 40 mph showed an increase in speed of 30+ mph, downhill. When going downhill the vehicle will increase in speed with the engine rpm's remaining at 1500 rpm's, 1500rpm = 40 mph. This clearly shows the cruise control is not releasing the throttle and not downshifting to slow the vehicle down, as standard cruise does. This is my second request for help, please look into this problem. Thanks for your help, george ferise.

My wife purchased 2014 Infiniti qx-60 SUV on January 23, 2014. She noticed when setting the intelligent cruise control at 40 mph the vehicle will pick-up speed going downhill. Depending on the length and grade of the hill the vehicle will increase as much as 30+ mph. When I drove the vehicle I noticed the engine rpm's remained at, 1500 rpm's, but the speed would continue to increase. On March 18,2014 I made a visit to dealership and met with the service consultant and the service manager. I explained what I experienced and asked if they could look into it for me. When I picked up the vehicle I was told they were unable to duplicate my concern. I then contacted Infiniti consumer affairs via email and explained my concern. I received a phone call from the consumer affairs person, and was told to call the dealerships service manager to schedule a test drive of the same model. I found it to have the same problem as my wife's car. I call the consumer affairs person at Infiniti and told him what I found. He explained that was how the cruise control was designed and is normal. On November 19,2014, I request to be notified when the Infiniti representative would be at the dealership. The Infiniti representative happen to be in the services managers office so I explained my problem to them. The service manager suggested we go for a test drive, and he drove. He set the intelligent cruise control at 40 mph, when we started downhill the vehicle picking up speed. When we reached the bottom we continued to pick up speed, almost 30 mph. The service manager contacted the Infiniti technical support group and explain what he experienced, and was told that this is normal. Sections 5-53 - 5-56 in the owner's manual states under the warnings "on steep downhill roads the vehicle may go beyond the set vehicle speed and frequent braking may result in overheating the brakes". (out of room).