2018 Kia Niro: Recalls, Problems & MPG
Here are the deets on the 2018 Kia Niro: 3 recalls, 60 owner complaints and up to 49 mpg combined.

Recalls
3 vehicle recalls from the manufacturer. Repairs are free. Check your VIN to see if one is still open on your car.
Hybrid system Vehicle recall #18V666000 · 2018 · 27,030 vehicles
What's wrong: The main relay within the power relay assembly (pra) May have inadequate connections between its contacts, causing increased electrical resistance.
Why it matters: The increased electrical resistance can overheat the rear seat which is above the pra, increasing the risk of a fire.
The fix: Kia will notify owners, and dealers will inspect the power relay assembly (pra) for damage. If no damage is found, the main relay will be replaced. If damage is found, the pra will be replaced. These repairs will be performed free of charge. The recall began November 23, 2018.
Hybrid system Vehicle recall #22V836000 · 2022 · 27,030 vehicles
What's wrong: The main relay within the power relay assembly (pra) May have inadequate connections between its contacts, causing increased electrical resistance, which can overheat the rear seats.
Why it matters: Overheated rear seats increase the risk of a fire.
The fix: Dealers will inspect the pra and replace either the pra or the main relay, as necessary, free of charge. Owner notification letters were mailed January 9, 2023.
Transmission & drivetrain Vehicle recall #23V534000 · 2023 · 121,411 vehicles
What's wrong: Kia america, Inc. (Kia) is recalling certain 2017-2022 niro and 2018-2022 niro plug-in hybrid vehicles. Fluid May leak into the printed circuit board inside the hydraulic clutch actuator, which can result in an engine compartment fire.
Why it matters: A fire increases the risk of injury.
The fix: Dealers will inspect and replace the hydraulic clutch actuator as necessary and install a new fuse, free of charge. Owner notification letters were mailed December 29, 2023.
Most-reported problems
Owner complaints filed with NHTSA, by component. One complaint can list several components. 0 mention a fire, 4 injuries and 0 deaths were reported.
What owners describe
- Transmission & drivetrain (19): the most common themes are warning light on (4), hard / delayed shifting (4).
- Electrical (18): the most common themes are electrical failure (12), warning light on (5), fire / smoke (4).
- Engine (17): the most common themes are fire / smoke (6), electrical failure (6), overheating (5).
- Other / unknown (11): the most common themes are electrical failure (5), fire / smoke (3).
The 2018 Kia Niro has 60 owner complaints, ranking #2 of 10 Niro model years for complaints (1.7× the average Niro year). Complaints peaked in 2023 (14 filed that year). The typical problem showed up when the car was about 5 years old, at a median of 27,290 miles. Neighboring years: 2017 (82 complaints, 4 recalls), 2019 (56 complaints, 1 recalls).
Engines & fuel economy (EPA)
| Engine | Transmission | Drive | City | Hwy | Comb. | Fuel |
|---|---|---|---|---|---|---|
| 1.6 L 4-cyl hybrid | Automatic (AM6) | Front-Wheel Drive | 51 | 46 | 49 | Regular |
Want the full repair deets? Get the factory manual.
Recall and complaint data tells you what goes wrong. A service manual tells you how to fix it: torque specs, wiring diagrams, fluid capacities and step-by-step procedures for the 2018 Kia Niro.
Closest thing to the factory manual for most years. Pay once, keep it.
Most $25–$78, one-timePro-shop repair procedures, wiring diagrams and TSBs for your exact car.
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FAQ
Does the 2018 Kia Niro have any recalls?
Yes. NHTSA lists 3 vehicle recalls for the 2018 Kia Niro. Recall repairs are free at any dealer, no matter how old the car is. Check your VIN at nhtsa.gov/recalls.
What are the most common 2018 Kia Niro problems?
Owners have filed 60 complaints with NHTSA. The most-reported areas are transmission & drivetrain (19), electrical (18), engine (17).
What gas mileage does the 2018 Kia Niro get?
EPA ratings run up to 49 mpg combined (1.6 L, Automatic (AM6)), across 1 engine and transmission combos.
Where can I get a 2018 Kia Niro repair manual?
eManualOnline sells downloadable manuals, Mitchell 1 DIY and ALLDATAdiy sell online access to factory repair data, and Haynes sells printed guides and online access. Pick a download if you want to keep it, or a subscription for wiring diagrams and TSBs.