There are 2 stored owner reports matching the powertrain & transmission leading-label group for the 2021 Kia Rio in our NHTSA-sourced dataset. These are unverified consumer reports and may not reflect confirmed defects.
This group counts stored reports whose component label starts with one of this site's matching prefixes, ignoring case. Each matching report counts once within the group. Components mentioned later in the label or only in the narrative are not searched. How component counts work
Loaded 2 of 2 matching reports.
Open the full vehicle complaint log (all categories)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.
NHTSA source checks for this vehicle year
Checks are recorded separately for each dataset, not for the whole page. Dates use UTC. A missing check date does not mean no records exist.
Vehicle import recorded: Apr 28, 2026. This is the stored import date, not confirmation that every source was successfully refreshed.