If the flowers are like the bedding type than it is Impatiens sodenii var oliveri. These can get to 10 feet in the wild.

I think...

They have almost flourescent pink/purple flowers. I used to have orange ones just like it.

Sounds like one that I have as well. I dont know the cultivar name for it. I just call it Giant Walleriana. If mine is the same as yours mine is about 5 feet tall. I have been looking for other color forms of it but have only seen the one.

***It Sounds Like Balsam! (Touch Me Nots!) Not Reg. Impatiens!
As My Balsm/Touch Me Nots Grow Too Tall!!!
***I'm Looking For Some Mixed Impatiens Seeds For Next Year!!! (Can You "Help"?) ;-)

look at my impatients
I didn't know name and nobody around here has them, I found out today they are impatient glandulifera.

Here is a link that might be useful: mystery no more

I noticed this fall at our doctors' office the impatiens were close to 4ft high. They were regular bedding impatiens, single, in mixed colors. They were in full shade and you could see they were well watered and well fertilized. They were leggy, though, and not upright and branched. I'd never seen impatiens that high. In neighboring beds with more light the same type was planted and it was much more normal in height. Still impressive, though.