Check Engine Light On problems of the 2007 Ford Five Hundred

My 2007 Ford Five Hundred sel fwd with the 3. 0 v-6 (81,421 miles) and 6 speed automatic transmission will intermittently surge forward or backwards without gas pedal application when idling in gear. It is as if I floored in a jackrabbit start. It does not do this every time that the car goes to idle in drive or reverse (for example, if I am in traffic at a stoplight) but it will do this at least once every time I drive. I have had to keep my right foot firmly on the brake pedal while backing or in a parking lot to keep the car from hitting pedestrians, other cars, sign poles in parking lots and my carport's wall. It will suddenly rev up when in either drive or reverse without my foot on the gas pedal and try to move in an uncontrolled manner. It may only do it once or it may do it three or four times in just as many seconds. I was unaware of this problem and nearly hit another car the first time this happened. There was no warning. No check engine light activated. My car is equipped with a tachometer, I have seen it jump as high as 2000 rpm from a 750 rpm idle and then fall right back to 750. The fact that I have not hit anyone yet is proof that this is not a pedal misapplication error, but my concern is that an inexperienced driver or someone who is unaware of this defect will be surprised by it and kill or injure themselves or someone else. This is the first time I have ever owned a vehicle with such a problem I took my car to my local Ford dealer and was told that the problem is a defective throttle body which is being replaced tomorrow. I researched this problem on the internet and have found reports that the replacement part is no better than the original. The fact that a defective part can cause a vehicle to act in such a dangerous manner is symptomatic of a factory defect and should be acted upon by the NHTSA as soon as possible.