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EnginePart report

2018 Kia Niro Engine Problems

Complaints
17about this part
Share
28%of 60 total for the year
Median mileage
62,115miles
Trend
RisingComplaints filed in the last 3 full calendar years are at least 25% higher than in the 3 years before.

NHTSA recorded 17 complaints about the engine of the 2018 Kia Niro, 28% of the 60 complaints for this model year. Where a mileage was given, the median is 62,115 miles.

Example complaints

Selected from NHTSA records; personal details are removed. They are consumer reports, not findings.

“I was driving on the freeway. After slowed down and stopped completely, suddenly it lose power to run. Trying to step deeper the gas pedal, but no reaction at all. After turn off and turn on engine few times, it can run again, but this time, the real problem occur. The engine sounds so loud..it's hybrid car supposed to so quiet (that's what sounds usually). Later on, I found out how to still can drove it, but with high risk suddenly lose power on the street. Later found out, when the car in motion, the hybrid system didn't worked completely, and the transmission sound very rough. …”

NHTSA complaint #11222226, filed 2019-06, 10 miles

“Engine/transmission becomes very sluggish as temperatures drop and the transmission seems to be engine braking the vehicle, making coasting nearly impossible. Putting the vehicle in neutral allowed the car to normally coast but once back in drive, acceleration was taxing. The vehicle lacks any power and is ruining the fuel economy trying to get the car up to speed.”

NHTSA complaint #11058078, filed 2018-01, 4,230 miles

“On March 28, 2023 the vehicle HEV warning light came on. I called the dealership where I was informed they did not have any mechanics available to look at it until August. No one to work on Hybrid. I then took it to a mechanic shop, And I was informed to take it to the dealer. I could not drive the vehicle. I called KIA, Temple Hills back, I was told if you tow the vehicle here it will just sit. …”

NHTSA complaint #11549759, filed 2023-10

“Just before Hurricane Helene, I brought my 2018 Kia Niro Hybrid to Asheville Kia (NC) after noticing coolant loss and white smoke coming from the exhaust. The dealership charged me $1,400 for a repair involving new gaskets and the EGR cooler. Within a month, the same symptoms returned. I returned to the dealership and explained I believed the original issue had not been resolved. I had done research and found reports of similar problems in other Niro Hybrids. …”

NHTSA complaint #11688703, filed 2025-09

“The car can slow down suddenly in the middle of traffic even if I accelerate. The engine has a problem according to the mechanics who was trying to fix my car twice without succes. The car does not hold coolant liquid for more than 15 minutes. It looks like the coolant is staying somewhere in the engine. It overheats too. Yes the car is available for inspection upon request. It's a high risk because the car can suddenly slow down in the middle of traffic or when leaving a light turned green. And the last time I drove it there a weird smell. …”

NHTSA complaint #11517087, filed 2023-04

Related service bulletins

Engine: other model years

YearComplaintsShare of year
2025212%
2024220%
202349%
2022619%
2021222%
2020923%
20191018%
20181728%
20172935%

Other parts of the 2018 Kia Niro

Transmission and drivetrain
19 complaints
Electrical system
18 complaints
Other or unknown
11 complaints
Brakes
6 complaints
Vehicle speed control
4 complaints
Body and structure
3 complaints
Exterior lighting
2 complaints
Fuel system
2 complaints
Air bags
1 complaints
Engine cooling
1 complaints
Seats
1 complaints

← All problems reported for the 2018 Kia Niro

About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 27, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.

To check a specific vehicle for open recalls, use its VIN at nhtsa.gov/recalls. Methodology