2004 Mercury Sable Engine problems

Tl* the contact owns a 2004 mercury sable. While driving at high speeds, the rpms increased without warning. The vehicle surged forward and exhibited rapid acceleration. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure. The failure mileage was approximately 135,000.

Started sudden acceleration while driving at 25 mph. Pressed hard on brakes to stop, put it on park mode. Still rpm was around 4000. Turned off engine. When cranked back, rpm kept on increasing without foot on accelerator. Tapped hard on accelerator couple of times, rpm went back to normal. *Tr

While driving and I go over 50 mph my car will speed up which cause the throttle cable to come apart an d the engine or transmission speeds up. *Tr

My mercury sable 2004 began accelerating on its own. The first time I was cruising at 35mph and had trouble stopping at a stop sign. Braking caused a vibration the rpm's were not going down. Driving further I noted the car would accelerate by itself. Tapping the the gas pedal quickly sometimes caused the rpm's to go back to normal. I took the vehicle to a local garage and had the throttle (cables, etc) checked. All were reported ok. The issue has happened off and on but yesterday (11/28/12) was the worst. I did...

While driving to work, I smelled burning plastic. I rolled up the window thinking it was another vehicle. A few minutes later I noticed an odd melting look on the rear windshield, and a stronger burning plastic smell. Immediately I turned off the rear defrost, and cracked the window to let the fumes escape. Approximately a mile later (while driving 70 mph) the rear windshield exploded. The glass initially stayed intact, but prior to me driving to the closest dealership (3 miles from that point), the shards began falling into the back seat of the vehicle. I am grateful there was no one in the back seat. *Tr