2018 Kia Optima problems and complaints

Owners have filed 232 complaints with NHTSA about the 2018 Kia Optima. The most-reported areas: Engine (131), Unknown Or Other (37), Electrical System (33).

Key takeaways

  • 232 owner complaints on file with NHTSA.
  • 10 involve a crash, 10 a fire, 9 reported injuries.
  • Complaints are unverified owner reports; recalls are confirmed defects.
Complaints by component
ComponentComplaintsShare
Engine13156%
Unknown Or Other3716%
Electrical System3314%
Power Train188%
Service Brakes177%
Engine And Engine Cooling146%
Exterior Lighting146%
Fuel/Propulsion System136%
Steering125%
Vehicle Speed Control104%
Air Bags94%
Structure73%

One complaint can name several components, so shares add up to more than 100%.

NHTSA 5-Star crash ratings
VersionOverallFrontSideRollover
2018 Kia Optima 4 DR FWD5/55/55/55/5

Latest complaints, as filed

Owner-written and unverified by NHTSA.

Engine - filed 2026-09-08

The contact owns a 2018 Kia Optima. The contact stated that upon starting the vehicle, the vehicle jerked abnormally. The failure persisted while driving, and the vehicle lost motive power. The contact was able to restart the vehicle; however, the failure persisted while driving. The vehicle was towed to a dealer to be...

Engine - filed 2026-08-20

The contact owns a 2018 Kia Optima. The contact stated that while driving at an undisclosed speed, the vehicle failed to accelerate and failed to exceed 52 MPH. The vehicle shut off. The contact stated that the engine was running rough while stationary and the vehicle shut off without warning. The vehicle was taken to ...

Engine And Engine Cooling - filed 2026-07-22

See attached document for complaint.

Diagnose it yourself

As an Amazon Associate we earn from qualifying purchases, at no extra cost to you.

More for the 2018 Kia Optima

Complaints are reports filed by owners with the National Highway Traffic Safety Administration. NHTSA publishes them without verifying them, and counts rise with how many cars were sold, so compare years of the same model rather than different models. Crash ratings are NHTSA's own 5-Star Safety Ratings results.