NHTSA vehicle safety data

2018 Kia Optima Recalls, Ratings & Complaints

The 2018 Kia Optima has 2 NHTSA recall campaigns and 233 owner complaints on file as of November 3, 2026. Recall repairs are usually free at an authorized Kia dealer.

NHTSA also files the 2018 Kia Optima separately as Optima Hybrid — 2 recall campaigns, Optima Phev — 2 recall campaigns.

NHTSA recall and complaint data for the 2018 Kia Optima, plus NCAP crash-test ratings. Recall data is refreshed daily from NHTSA.

Pre-purchase inspection checklist → Reliability & 5-year cost forecast →

2018 Kia Optima owner complaints

Owners have filed 233 complaints with NHTSA about the 2018 Kia Optima, describing incidents dated January 20, 2018 to August 8, 2026.

Most-cited components

Engine 144 complaints
Unknown or Other 38 complaints
Electrical System 33 complaints
Power Train 19 complaints
Service Brakes 17 complaints
Exterior Lighting 14 complaints

Of the 233 complaints on file, 10 report a crash and 10 a fire; across all 233 complaints, owners report 9 injuries (owner-reported, not verified by NHTSA).

Newest complaints

ODI #11772835 · Filed October 21, 2026
My 2018 Kia Optima has the Theta II 2.4L engine. In February 2026, the dealer performed an engine/powertrain computer reprogramming. In August 2026, the engine failed and the vehicle was taken to an authorized Kia dealer, where the engine was replaced under the Theta II engine warranty. The vehicle…
ODI #11762830 · Filed September 8, 2026
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…
ODI #11758363 · Filed August 20, 2026
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…

Read all 233 complaints

Owner-reported

2018 Kia Optima mileage at failure

73 of the 233 complaints on file for the 2018 Kia Optima give the vehicle's mileage when the problem happened.

Mileage at failure by component, from owners' complaints to NHTSA
Component	Median	Middle half	Based on
Engine	Median 90,000 miles	Middle half 65,000–110,000 miles	Based on 42 complaints

A component's median is its 50th percentile, and its middle half runs from its 25th to its 75th percentile.

Owners give the mileage themselves, often as a round number, and NHTSA doesn't check it. A complaint that names several components counts under each one, and mileages that can't be right, such as 999,999, or 50 miles on a five-year-old car, are left out.

These figures describe the complaints owners filed. They don't predict when a particular vehicle will have a problem, and vehicles that never had one aren't counted.

Most complaints NHTSA received since May 17, 2021 give no mileage. So that they aren't undercounted, each one received since then that gives a mileage also stands in for those that gave none, which can put a component's median above most of the mileages it is based on.

Mileage from NHTSA's complaints file of October 31, 2026. How these figures are worked out

NHTSA defect investigations

NHTSA's investigations file lists the 2018 Kia Optima in 2 investigations. A listed model year means only that an investigation names it; it says nothing about any particular vehicle. An open investigation is not a finding that a safety defect exists, and NHTSA can close one without a recall.

Engineering Analysis EA19-001: Electrical overstress
Closed September 19, 2024
- Recall 20V-024
Defect Petition DP22-003: Loss of Motive Power
Closed December 12, 2023

Open and recently closed NHTSA defect investigations

Trunk Emergency Release May Fail/FMVSS 401

NHTSA #23V594000 · Latches/Locks/Linkages — Trunk Lid — Latch · NHTSA notice

Reported August 24, 2023 · Kia America, Inc.

Potentially affected: 319,436 vehicles

Repair completion: 47.58% (latest rate the manufacturer reported to NHTSA; dataset updated November 3, 2026)

Kia campaign SC278 · Owners notified October 19, 2023

Defect description

Kia America, Inc. (Kia) is recalling certain 2016-2017 Rio, 2016-2018 Optima, 2017-2018 Optima Hybrid and Optima Plug-in Hybrid vehicles. The trunk latch base may crack, preventing the opening of the trunk from the inside. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 401, "Internal Trunk Release."

Safety consequence

A person inside the trunk compartment may become trapped, increasing their risk of injury.

Manufacturer remedy

Dealers will replace the trunk latch base subassembly, free of charge. Owner notification letters were mailed October 19, 2023. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC278.

Notes

Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.nhtsa.gov.

Voltage Protection Device may Activate

NHTSA #18V161000 · Hybrid Propulsion System · NHTSA notice

Reported March 8, 2018 · Kia Motors America

Potentially affected: 1,710 vehicles

Repair completion: 81.71% (latest rate the manufacturer reported to NHTSA; dataset updated November 3, 2026)

Kia campaign SC162 · Owners notified May 3, 2018 · Vehicles built August 25, 2016 – September 11, 2017 (per NHTSA)

Defect description

Kia Motors America (Kia) is recalling certain 2017-2018 Kia Optima hybrid vehicles. These vehicles are equipped with a Voltage Protection Device (VPD), designed to protect the high voltage battery module, that may activate inadvertently.

Safety consequence

If the VPD activates while the vehicle is being operated in Electric Vehicle (EV) mode, there may be a loss of power, increasing the risk of a crash.

Manufacturer remedy

Kia will notify owners, and dealers will remove the VPD switch and install two newly designed Battery Management Systems (BMS) that contain Overvoltage Protection Devices (OPDs), free of charge. The recall is expected to begin May 2018. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC162.

Notes

Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.safercar.gov.

2018 Kia Optima 4 DR FWD

out of 5

Overall Safety Rating

Frontal Crash

Driver: 5, Passenger: 4

Side Crash

Driver: 5, Passenger: 5

Side Pole

Rollover

10% rollover risk

Safety Technology

Electronic Stability Control Forward Collision Warning (Optional) Lane Departure Warning (Optional)

2 investigations

233 owner complaints have been filed with NHTSA for the 2018 Kia Optima.

Power Train; Unknown or Other; Engine

ODI #11772835

Incident: August 8, 2026 · Filed: October 21, 2026

My 2018 Kia Optima has the Theta II 2.4L engine. In February 2026, the dealer performed an engine/powertrain computer reprogramming. In August 2026, the engine failed and the vehicle was taken to an authorized Kia dealer, where the engine was replaced under the Theta II engine warranty. The vehicle was at the dealer from August 8 until the repair was completed on September 29, 2026. When I picked up the vehicle on October 9, it felt shaky and vibrated on the drive home. On October 11, the vehicle began giving off a distinct, unfamiliar smell that is not like burning fuel or oil. On October 21, I found the vehicle leaking an opaque, milky tan fluid onto my garage floor. The type and source of the fluid are UNKNOWN. I have photos of the leak. My family and I have stopped driving the vehicle because we believe it is unsafe. We were driving it with our children before these symptoms appeared. Given the history of Theta II engine failures, we are concerned about the risk of engine failure, stalling, or fire while driving. The new symptoms have not yet been diagnosed or confirmed by a dealer. I am arranging for the vehicle to be towed to a Kia dealer for warranty diagnosis. The vehicle and leak are available for inspection. I have reported these issues to the manufacturer under an open customer case.

Engine

ODI #11762830

Incident: July 8, 2026 · Filed: September 8, 2026

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 repaired under an unknown recall for an engine software update and key fob replacement; however, the dealer failed to honor the recall repair and recommended purchasing a new vehicle. The manufacturer was contacted by phone, and a case was filed. The failure mileage was approximately 126,000. The VIN and License plate number were unavailable.

Engine

ODI #11758363

Incident: February 1, 2026 · Filed: August 20, 2026

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 an Auto Parts Store, where it was diagnosed, and it was determined that the vehicle was in LIMP Mode with knock sensor codes displayed. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was approximately 136,000.

Engine and Engine Cooling

ODI #11752131

Incident: June 3, 2026 · Filed: July 22, 2026

See attached document for complaint.

Air Bags; Seat Belts

ODI #11751435

Crash 1 injury

Incident: July 14, 2026 · Filed: July 19, 2026

I was run off the road by a drunk driver I hit a tree at 35MPH MY AIR BAGS DID NOT DEPLOY NOR DID MY SEAT BELT LOCK!!!! I NOW HAVE MULTIPLE INJURIES I HAVE BROKEN BONES ALL THROUGHOUT MY FACE!!!!! A SEVERE CONCUSSION!!!!! Any time I call the the customer care center and try and get information or call someone I either get hung up or gave the run around and then hung up on my mother in law has also tried calling and have received the same response this is so unacceptable and unprofessional.

Engine

ODI #11749282

Incident: May 23, 2026 · Filed: July 9, 2026

I’ve had my 2018 kia optima for round about two years.I only got this car because they refused to replace my previous engine on my 2015 Kia optima,even though I had a warranty but that’s another story(Kia on the Blvd).This car have given me problems from the start.Going through oil in less than a month,which they can never find a leak,not being able to go over a certain speed before I start to hear noises.Ive complained about noises,they act like they can’t hear,and said nothing is wrong with the engine when previously checked.My check engine light has came on twice and both times the car was malfunctioning on the highway resulting in me have to get a tow.First it was plugs replacement now I need a whole new engine.I really don’t know what to do at this point.I believe they sold me a faulty car

Service Brakes

ODI #11748040

Incident: January 6, 2026 · Filed: July 2, 2026

Purchased vehicle from a used car dealership. Had it a few months before brake pedal started losing pressure and going to floor. Had master cylinder replaced. A few months later, brake light started coming on when accelerating. New master cylinder had leaked into brake booster. Had master cylinder replaced along with brake booster. A few weeks later and brake pedal is losing pressure again

Engine

ODI #11746528

Incident: June 15, 2026 · Filed: June 25, 2026

The car burns oil within a week of getting an oil change. It was only driven a 200 miles before all of the oil was burned out. This has been a consistent issue with this car that the oil burns at an extreme rate. This is a safety risk as it could lead to engine overheating, the engine could stall out due to the fast burning of the oil, or a potential fire hazard while driving. The oil light will come on for a second and at that point, the oil is already EXTREMELY too low. I brought the car to the mechanic and they have told me multiple times that there is no leak or anything. The mechanic says that the car simply is burning oil too fast.

Engine and Engine Cooling

ODI #11745997

Incident: August 29, 2018 · Filed: June 23, 2026

The contact owns a 2018 Kia Optima. The contact stated that while driving at an undisclosed speed, there was an abnormal odor and a knocking sound coming from the engine. The vehicle was taken to the dealer; however, the dealer was unable to duplicate the issue. The vehicle was not repaired. The issue persisted. The contact stated that the vehicle was later returned to the dealer to be repaired under a service campaign involving the engine control unit (ECU). Shortly after the vehicle was repaired, the ECU failure message was displayed. The vehicle subsequently became inoperable. The vehicle was not repaired. The manufacturer was notified of the issue. The approximate failure mileage was 1,500.

Unknown or Other

ODI #11743257

Incident: June 9, 2026 · Filed: June 10, 2026

2018 Kia Optima Dealer Ed Voyles Kia Smyrna began Recall SC340. Vehicle drove in running. Dealer flashed ECM software, discovered non-original engine/ECU. Vehicle now won’t start. Dealer document states 'will not start after recall.' Dealer refuses to restore to running condition citing prior repairs. This violates 49 USC 30120

Other Kia Optima model years

Check your 2018 Kia Optima VIN

Not every recall applies to every VIN in a given year. Enter the 17-character VIN from your Kia Optima at nhtsa.gov/recalls to see whether your specific vehicle has an unrepaired recall.

Check a Kia VIN