2021 Kia K5 Problems, Recalls & Reliability
Verdict
GoodComplaint Index
25/100
#4 most-complained of 5 K5 years
Based on NHTSA complaints per model-year, not a reliability rating. Methodology
The 2021 Kia K5 has a Complaint Index of 25, the second-lowest among the 5 model years with data, and ranks 4th worst of 5, earning a "Good" verdict relative to other K5 years. It has 167 NHTSA complaints and 6 recalls, led by Fuel System issues (56 complaints, 34% share).
- Complaints
- 167
- Recalls
- 6
- Crashes / fires
- 8 / 2
- Injuries / deaths
- 7 / 1
- NHTSA overall rating
- 5 / 5 ★
- EPA combined MPG
- 30
- 26.5 city / 35.5 hwy
Top 2021 Kia K5 problems
NHTSA owner complaints by component group. Groups with 15+ complaints have their own page.
- Fuel System56 (34%)
- Electrical System47 (28%)
- Engine33 (20%)
- Other32 (19%)
- Structure & Body18 (11%)
- Transmission & Powertrain18 (11%)
- Airbags10 (6%)
- Brakes9 (5%)
- Collision Avoidance & Cameras9 (5%)
- Lane Departure9 (5%)
What owners report
- Airbags reportedly fail to deploy in moderate-to-severe crashes, including frontal, rear, and broadside impacts.
- Electrical system complaints include an under-hood fire shortly after highway driving and burning blower motor fuses/relays tied to a warranty extension.
- Owners report the R-MDPS power steering system shuddering and becoming rigid during low-speed turns, in one case leading to a crash.
- A transmission fluid leak was found on a nearly new vehicle within days of purchase, requiring dealer service.
- Some owners noted unexplained warning lights linked to computer chip issues, and abnormal wind noise from rear doors at highway speed.
2021 Kia K5 recalls
6 NHTSA recall campaigns list this model year.
- NHTSA 25V794000Nov 17, 2025Fuel System250,547 vehicles
Fuel system, gasoline
Kia America, Inc. (Kia) is recalling certain 2021-2024 K5 vehicles. A damaged check valve can allow air to enter the fuel tank, causing it to expand and contact hot exhaust components, melting the tank.
Risk: A melted fuel tank can leak, increasing the risk of a fire.
Remedy: Dealers will replace the check valve. The fuel tank will be inspected for damage and replaced as necessary. All repairs will be performed free of charge. Owner notification letters were mailed January 16, 2026. Owners may contact Kia customer service at 800-333-4542. Kia's number for this recall is SC356. Vehicle Identification Numbers (VINs) involved in this recall will be searchable on NHTSA.gov beginning December 1, 2025.
- NHTSA 23V149000Mar 7, 2023Airbags188,912 vehicles
Air bags:side/window:curtain
Kia America, Inc. (Kia) is recalling certain 2021-2023 K5 vehicles. The side curtain air bags may have been installed incorrectly, causing them not to deploy properly in the event of a crash.
Risk: Air bags that do not deploy as intended can increase the risk of injury in a crash.
Remedy: Dealers will inspect and reinstall the side curtain air bags, as necessary, free of charge. Owner notification letters were mailed April 7, 2023. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC263.
- NHTSA 22V760000Oct 11, 2022Transmission & Powertrain69,038 vehicles
Power train:automatic transmission
Kia Motors, Inc. (Kia) is recalling certain 2021-2022 Sorento and 2021-2023 K5 vehicles. The vehicle's "fail-safe" limited-mobility drive mode may be impaired, when prompted by a transmission oil pump malfunction, which can result in a complete loss of drive power.
Risk: Loss of drive power increases the risk of a crash.
Remedy: Dealers will inspect and replace the transmission, as necessary. Dealers will also update the transmission control unit software. All repairs will be performed free of charge. Owner notification letters were mailed December 9, 2022. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC250.
2021 Kia K5 fuel economy and fuel cost
- City
- 26.5 MPG
- Highway
- 35.5 MPG
- Combined
- 30 MPG
- Annual fuel cost (EPA)
- $2,175
- 15,000 mi/yr
- Fuel
- Regular
- Current regular gas
- $4.32/gal
- national avg.
EPA figures; median across configurations of this model year. Estimate your own cost with the fuel cost calculator.
2021 compared with other K5 years
Frequently asked questions
- Is the 2021 Kia K5 reliable?
- Based on NHTSA owner complaints and recalls, the 2021 K5 has a Complaint Index of 25 and ranks 4th worst of 5 model years, which places it in the "Good" category relative to other K5 years.
- What are the most common problems with the 2021 Kia K5?
- Fuel System complaints lead with 56 reports (34% share), followed by Electrical System with 47 complaints (28%) and Engine issues with 33 complaints (20%), according to NHTSA data.
- Does the 2021 Kia K5 have any recalls?
- NHTSA lists 6 recalls for the 2021 K5, covering the fuel system (check valve and fuel pipe leaks), side curtain airbags, transmission fail-safe mode, power steering software, and an airbag occupant detection unit.
- How does the 2021 K5 compare to the 2022 and 2023 K5?
- The 2021 K5 has a lower Complaint Index (25) than the 2022 (100, Avoid) and 2023 (75, Avoid) model years, making 2021 a comparatively better choice among K5 years.
- What is the fuel economy of the 2021 Kia K5?
- The 2021 K5 gets an EPA-rated 30 mpg combined (26.5 city / 35.5 highway), with an estimated annual fuel cost of $2,175.