Engine complaints by model year
Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
What owners report
My 2023 Kia Niro Hybrid EX has experienced multiple warning messages and unresolved concerns after previous repairs. After the first recall repair, I began receiving intermittent warning messages while driving. The messages appeared briefly and disappeared before I could safely document them. After a second repair, the transmission was replaced. Shortly afterward, the vehicle displayed an overheating warning. I returned to the dealership, but they stated they could not find a problem. While traveling out of state, on July 6, 2026, the vehicle displayed warnings indicating that the 12V battery needed to be charged. On July 8, 2026, the vehicle would turn on, but the engine would not start or operate. Multiple attempts to jump-start the vehicle failed, including using a portable jump pack, another vehicle, and assistance from a tow truck driver. …
This May of been a cause of a defective Harness Assembly that has taken a few tries to get repaired (Harness is fixed but problem still continues randomly). Since then, my car has stalling problems, randomly, sometimes multiple time in one drive. I have no way to replicate it on my own just that it "can happen" anytime and has subjected me to waiting on the side of the road for the engine computer to "reset" or needs for a tow. Ive been in the dealership at least twice for this with a 3rd this week. Me and the dealer thought it may go away with the new harness installed but it still remains
The vehicle has a recurring P0420 code ("Catalyst System Efficiency Below Threshold Bank 1"). A boroscope inspection at Ricardo Caballero Kia Santa Isabel (invoice #[redacted] dated December 5, 2025) confirmed internal disintegration of the catalytic converter, with physical pieces of the catalyst falling out when the exhaust pipe was removed. This failure appears related to Recall 23V534 (SC276) and TSB PS709 (overheating / coolant boiling issues in 2017-2022 Niro Hybrid models). Motorambar, Inc. (official Kia distributor in Puerto Rico) has ignored my warranty claim since December 2 and December 22, 2025 (more than four months). Motorambar is now refusing to authorize a courtesy loaner vehicle at the dealer Ricardo Caballero Kia Santa Isabel, claiming the tests will take less than 5 days. This leaves me without transportation. …
Vehicle with code p0420, Kia dealership technician say: the problem was the spark, proceeded to change it and clear code. Check engine turn on again, the same person say: it's a ring piston, the car was leaked engine oil to exhaust and he see blue smoke, no evidence for part of dealership and dealership never mention the car was consuming excessive engine oil. I mentioned the law of emission to change the catalyst and the boss say: I can't change it but the problem will be come but never do anything to change it. In other dealership Kia the technician dismantle the exhaust and see ceramic part coming from the catalyst, his recommendation is change it. Dealership make a formal petition to motorambar distributor official ok Kia in PR and motorambar refuse to change the part with the evidence provide by dealership: technician report and photos. …
The contact owns a 2020 Kia Niro. The contact stated that the oil change due in 700 miles message was displayed. The contact stated while driving 55 MPH to have an oil change performed, oil change service at 55 MPH, the contact heard an abnormal popping sound. The contact stated that the low oil pressure warning light became illuminated. The contact stated while approaching the Auto Shop for the oil change, the vehicle lost motive power and made another abnormal sound. The independent mechanic informed the contact that the engine might have failed and referred the contact to the dealer for assistance. The vehicle was towed to the dealer, where the contact was informed that the oil plug had separated, causing a significant oil leak and engine damage. The dealer determined that the engine needed to be replaced. The vehicle was not repaired due to the cost. …
The contact owns a 2020 Kia Niro. The contact stated that while driving 79 MPH, the thermostat displayed that the engine was running hot and there was white smoke coming from the front of the vehicle, with the check engine warning light illuminated. Upon inspection, the contact became aware that a hose underneath the radiator was disconnected, and coolant was leaking from the hose, and the dipstick had dislodged into the engine. The contact stated that while accelerating from a complete stop or while decelerating, the vehicle jolted forward. The local dealer was contacted; however, the vehicle was not diagnosed or repaired. The manufacturer was notified of the failure. The failure mileage was 98,000.
The contact's customer owns a 2019 Kia Niro LX. The contact stated that his customer stated that the vehicle overheated. The check engine warning light was illuminated. The vehicle was taken to an independent mechanic who replaced the converter. The vehicle was repaired, but the failure recurred. The owner stated that the vehicle was randomly stopping. The vehicle was taken back to the independent mechanic. While test driving at 15 MPH, the brakes were operating as designed, and then after several attempts, the brake pedal was applied and depressed to the floorboard, and the driver crashed into a parked BMW X5. There were no warning lights illuminated. The brakes were inoperable. The air bags deployed. There were no reported injuries, fire or police report filed. The local dealer was contacted, but the vehicle was not diagnosed or repaired. …
The contact owned a 2019 Kia Niro. The contact stated while driving at an undisclosed speed, the contact noticed a ticking and a popping sound coming from the vehicle. The contact's friend who was following behind noticed white smoke coming from the exhaust pipe. The vehicle was driven to the destination. The following day, the oil level was checked, and the contact stated that the oil level was low; however, there was no sign of an oil leak. The contact stated that when the vehicle was started and made a rattling sound. The contact turned the vehicle off and the vehicle was towed to an independent mechanic where it was diagnosed with a hole in the crankcase. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure and a case was filed. The failure mileage was approximately 120,000.
Frequently asked questions
Which Kia Niro years have engine problems?
By NHTSA complaints, the 2017 (33), 2018 (18), 2019 (13), 2020 (11) and 2022 (6) model years. Engine complaints make up 40% of all complaints for the 2017.
Is there a recall for Kia Niro engine problems?
No. NHTSA lists no engine & cooling recall for any Kia Niro model year. A widespread problem may still be covered by an extended warranty or a manufacturer service bulletin, so ask a dealer.
At what mileage do Kia Niro engine problems start?
Across all years, half of the complaints with a recorded mileage happened before about 81,000 miles; 30% happened before 50,000 miles.
What part fails most often?
Owners most often name the exhaust system (1 mentions).
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.