There are 2 owner-reported powertrain & transmission complaints for the 2021 Kia Rioin NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
Placed car in park got out to open a gate. Car took off forward even when shifter was in Park Position and almost ran a child over.
I had driven my wife to her school about 5 miles and headed back to my work another 5 miles when i tried to accelerate pass car I lost almost all power barely making it up a slight hill I kept going trying to make it to my house barely going 10 miles an hour. I thought the transmission had let go cause while I had the gas peddle floored i went at best 10-15 miles an hour I eventually parked the car I knew it would never make it up another slight hill. It was rowed to a nearby dealer where they could find no problem telling me it was just some bad gas. This sounds like what I read about today with a couple of other models of Kia.
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 26, 2026