A Prius moment.
 

The wife said the other day her 2009 Aspen did something strange. When she came up to a stop sign and put on the brakes the engine started to accelerate. The harder she pushed on the brake the more the engine accelerated. She was almost into the intersection with traffic coming when it stopped and went back to normal. My first thought was she had here big foot on both pedals. Iv'e driven the car for a week with no mishaps or hints of any. Borrowed a friends expensive scan tool and there where no codes. Has anyone heard of this happening before? The wife wants to sell the car.

Not likely that one foot could press both pedals, as the brake pedal is usually much higher than the gas pedal. Does she drive using both feet on the pedals? People who use their left foot on the brake have been known to tromp down hard with both feet at the same time. The brakes are several times more powerful than the engine, and you should be able to demonstrate to her that from a stopped position, the car will not move if the brakes are fully applied no matter how hard you step on the gas.

"Wife wants to sell the car." Once an irrational idea gets implanted, there's no rational way to displace it. Emotion conquers reason every time.

I set out to prove the two pedal one foot theory yesterday and was successful. The problem is that yes, the brake does sit higher than the throttle, up until you press on the brake. Then the brake pedal does drop below the throttle. So yes you can apply both brake and throttle at the same time. I'm surprised the safety watch dogs haven't caught that one. With all the throttle by wire vehicles out there, they haven't programed a throttle disconnect when the brakes are applied.