I have a kia rio 2012 with the same problems?

I am having the same exact issue. This is the second time bringing it to Kia. It was really, really scary. I am waiting for them to tell me anything...two weeks ago when I took it they said they couldn't find anything with the computer check and driving it around themselves. They sent me home with no diagnosis except that maybe it's the cold weather...I doubt that...because I DO always let it warm up. Have you found any answers? I'll keep you posted on my end. I'm looking online for similar probs with cars and will print out what I find and suggest they look at such possible probs...I'm really hoping that they don't blow this off or take a lazy way out. This is how people get hurt and/or sued. I'm not stopping this time...either they fix it bc it's under warranty or they give me a new car.

So I just got my car back today! They said it was the accelerator pedal...that it was sticking...and that the binding inside was getting stuck. They replaced the pedal for free because it was still under warranty. So far so good! :) I hope this stays this way for quite some time. I will keep you posted if anything changes! Suggest this to your mechanic and tell him that I have the same car!