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Owner complaints · Engine

2018 Kia Optima engine problems

152 of the 243 complaints owners filed with NHTSA about the 2018 Kia Optima name the engine (NHTSA’s “Engine” heading — the engine and its cooling system). Filed under the same heading: 97 manufacturer bulletins, 1 recall, 2 NHTSA investigations. Every figure below is a document in a federal file, linked; none is a failure rate, and none is a verdict on any one car.

152 complaints 63% of this model year’s 1 report a crash 9 a fire typically at 70k miles

What owners filed about the engine

Source: NHTSA complaint database

152complaints name the engine

1 of the 152 reports a crash · 9 a fire · 0 injuries. Self-reported, unverified.

Filed per year: 2019: 9 · 2020: 4 · 2021: 9 · 2022: 19 · 2023: 34 · 2024: 30 · 2025: 34 · 2026: 13

70kmiles, typically

Half of the 47 owners who gave an odometer reading reported the engine problem between 22,000 and 100,000 miles. A median of reports, not the life of a part.

63%of this model year’s complaints

243 complaints in all about the 2018 Kia Optima, 13 filed in 2026. The whole picture, every system →

Counts are owner reports to NHTSA, not verified defects, and scale with how many of these were sold; nothing here is a rate. NHTSA groups complaints coarsely, so “Engine” means the same area of the vehicle, not one fault.

Across model years: Kia Optima engine problems, every year on file →

In owners’ own words

Source: NHTSA complaint database

Filed with NHTSA by the people who own these cars, about the engine. Quoted as written, with anything identifying removed; unverified reports — what was said, not a finding that it was true.

The contact owns a 2018 Kia Optima Hybrid. The contact stated that while operating the vehicle, the message "Turn Engine Off Immediately" was displayed, and the vehicle decelerated to 35 MPH and stalled. The vehicle was towed to the local dealer who diagnosed that the engine was faulty and needed to be replaced.

Engine at 100,000 miles Apr 5, 2023 NHTSA owner report

I originally leased my 2018 Optima with 98 miles on it and bought it out at the end of my lease this was my second Optima, I also had 2 hyundai sonatas. Since i'm in sales I had the added mileage on it. At 98,000 miles the engine started ticking.

Engine at 98,000 miles Mar 2, 2021 NHTSA owner report

I leased 2018 Kia Optima ex. At 6399miles and 9650miles engine light on and car vibrates a lot. First service replaced spark plug and second time they replaced engine. This car was awarded as best initial quality award which has engine issues.

Engine at 9,650 miles Jun 25, 2020 NHTSA owner report

Engine turned off while driving without any warning, going straight, in city. Dealership can not duplicate or diagnose problem

Engine at 41,000 miles Jun 17, 2020 NHTSA owner report

I have never had any issues with my car, I get maintenance as scheduled so it's odd that this is even happening. On december 6th I went to move my car. I crank the car with no problem. I noticed it kind of hesistated slightly, but continued on with no problem.

Engine at 42,100 miles Dec 7, 2019 NHTSA owner report

What is on file about the engine

Source: NHTSA recalls, investigations and manufacturer communications

Recall filed under this heading

21V844000 Critical
Oct 29, 2021 · 10,731 vehicles
Kia Motors America (Kia) is recalling certain 2017-2018 Optima Hybrid and Optima Plug-In Hybrid vehicles. The connecting rod bearings inside the engine may wear prematurely, which can result in engine damage.

NHTSA investigations

DP22003 Loss of Motive Power
opened Sep 12, 2022 · closed Dec 12, 2023
The National Highway Traffic Safety Administration (NHTSA) received a letter dated July 13, 2022, petitioning the Agency to initiate a safety defect investigation into loss of motive power allegations attributed to oil drain pan assembly failures on certain Hyundai Motor America, Inc. and Kia America, Inc. vehicles spanning Model Years (MY) 2005-2021. The Petitioners cited examples of complaints i…
EA21003 Engine Fires
opened Dec 22, 2021 · closed Feb 5, 2024
On March 29, 2019, the Office of Defects Investigation (ODI) opened two Preliminary Evaluations (PE19-003 on Hyundai and PE19-004 on Kia) to broadly investigate incidents of non-crash fires (regardless of origin or operational status of the vehicle) on various model year Hyundai and Kia vehicles. During the PE investigations, Hyundai and Kia issued several recalls to address vehicle fires, includ…

97 manufacturer bulletins filed under this heading

SC340_TSB_R5 Emissions
Apr 4, 2026
VOLUNTARY EMISSIONS SERVICE CAMPAIGN: THETA II 2.4L GDI EMISSIONS: ECM LOGIC IMPROVEMENT (SC340 REVISION 5) - This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This bulletin provides information to upgrade the Electronic Control Module ‘ECM’ system software for certain 2016-2020MY Optima, 2016-20
TSB_ENG222_R8 Service bulletin
Apr 3, 2025
TECHNICAL SERVICE BULLETIN: EXCESSIVE OIL CONSUMPTION NU/GAMMA/THETA/KAPPA ENGINES - This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This bulletin provides information on diagnosing and/or repairing some 2011-2024MY vehicles (refer to the table on pages 9 and 10 for applicable models and engine
TSB_ENG222_R7 Service bulletin
Feb 28, 2025
TECHNICAL SERVICE BULLETIN: EXCESSIVE OIL CONSUMPTION NU/GAMMA/THETA/KAPPA ENGINES - This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This bulletin provides information on diagnosing and/or repairing some 2011-2024MY vehicles (refer to the tables on pages 8-9 for applicable models and engine), w

The 3 newest are listed; every one is on the model year’s page. Quote the document number at a service desk — it is a diagnosis the maker has already written down.

Trouble codes named on this system

P1326 P200A

Codes a bulletin or an owner’s complaint about the 2018 Kia Optima names on this model year; a code with a record of its own links it.

From here

Every 2027 model on file, by price Compare two vehicles, trim vs trim See what a VIN was priced at See what owners reported

Common questions

Source: NHTSA complaint database, recalls and manufacturer communications

Are engine problems common on the 2018 Kia Optima?

They are documented: NHTSA holds 152 owner complaints naming the engine on this model year (63% of everything owners filed about it), and 97 manufacturer bulletins, 1 recall, 2 NHTSA investigations are filed under the same heading. Whether it is a problem on one particular car is a diagnosis, not a count, and a count says nothing about how many were sold.

Is there a recall for the engine on the 2018 Kia Optima?

Yes — one campaign is filed under this heading: 21V844000. A recall is matched by VIN; check yours at nhtsa.gov/recalls.

When do engine problems show up on the 2018 Kia Optima?

Owners who gave an odometer reading reported it at a median of 70,000 miles; half of them between 22,000 and 100,000. That is when reports cluster, not the life of a part.

What does NHTSA's "Engine" heading cover?

The engine and its cooling system. Owners choose the heading when they file, so it says which area of the vehicle the complaint is about, not which part failed.