This problem sounds very familiar.

I was working when my family took ownership of the car for me while I was away.

I got home and my sister immediately told me I bought a crappy car. Angry and confused I asked her why.

She said it was sluggish and didn't go fast, slower than her old *** Saturn.

Come to find out her style of driving is keeping her hand on the shifter. With the Chrysler Autostick system she moved the shift lever when going over a bump into the Automanual mode and drove home in 1st...the whole way.

I don't know if I'm missing a method but as far as I know you need to pull over, move the shifter out of the automanual area and out of D to reset the system to regular automatic driving.