Most common 2018 Kia Optima Phev problems
Share of the 8 complaints; one complaint can involve more than one system. "~" is the median mileage when the problem started.
Kia Optima Phev complaints by model year
2018 Kia Optima Phev recalls (2)
Latches/locks/linkages › Trunk lid › Latch
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.
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.
Engine
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.
Remedy: Dealers will inspect the engine. If bearing damage is found, the engine will be replaced. Dealers will also install a software update containing a Knock Sensor Detection System (KSDS).
NHTSA defect investigations
Federal safety investigators have looked into 3 possible defects involving the 2018 Kia Optima Phev:
Engine Fires
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.
Pedestrian alert sounds
NHTSA received a petition on or about July 18, 2022, requesting that Federal Motor Vehicle Safety Standard (FMVSS) 141 be applied to all electric and hybrid vehicles operating in the United States. The petition can be reviewed at NHTSA.gov under ODI Number 11486072. FMVSS 141 establishes performance requirements for pedestrian alert sounds for motor vehicles.
Loss of Motive Power
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.
What 2018 Kia Optima Phev owners say
Engine & cooling
When I was driving on the highway on 2/14/2011 a "check hybrid system" warning came on, check engine light, triangle HEV light, a red battery light came on and car lost engine power. After my vehicle slowed traffic down due to not having power I was barely able to pull over to the side of the road by coasting the car to the shoulder. It would not accelerate what so ever not even with just the engine power. When I pulled over the big check hybrid system warning dissapeared and only the check engine light and triangle HEV light stayed on. I had my children in the car and almost caused an accident. It was towed to my home and after I connected it to the wall plug for an hour the lights dissapeared. …
Error message "check hybrid system. Turn off engine" with yellow caution triagle showing exclaimation point and HEV" came on, at highway speed vehicle dropped to from 65 MPH to 40 MPH suddenly, exited freeway, turned car off and restarted...vehicle had loss of propulsion, would not go over 20 MPH. Stop, at stop sign, and when I applied gas, the vehicle would not go over 10 MPH...once safely off the road, I turned engine off, towed to dealer. Dealer could not duplicate. 1 day after picking up the vehicle from dealer, same problem occurred. I returned the vehicle to the dealer for inspection...two weeks at the dealer and they say its a water pump.
Electrical system
The contact owns a 2018 Kia Optima PHEV. The contact's daughter stated that while driving at an undisclosed speed, the high systems temperature switching to hybrid mode message was displayed. The contact stated that there was a two-hour delay for a full charge. The vehicle was taken to the dealer but was not diagnosed or repaired. The dealer informed the contact that the fluids in the vehicle needed to be changed. The vehicle wasn't repaired; however, the failure recurred. The vehicle was taken back to the dealer, where it was not diagnosed or repaired. The contact was informed by the dealer to remove all the items located in the trunk of the vehicle. The vehicle was not repaired; however, the failure recurred. The vehicle was taken to the dealer, where it was diagnosed that the battery fan assembly had failed and needed to be replaced. The vehicle was not repaired. …
When I was driving on the highway on 2/14/2011 a "check hybrid system" warning came on, check engine light, triangle HEV light, a red battery light came on and car lost engine power. After my vehicle slowed traffic down due to not having power I was barely able to pull over to the side of the road by coasting the car to the shoulder. It would not accelerate what so ever not even with just the engine power. When I pulled over the big check hybrid system warning dissapeared and only the check engine light and triangle HEV light stayed on. I had my children in the car and almost caused an accident. It was towed to my home and after I connected it to the wall plug for an hour the lights dissapeared. …
Frequently asked questions
Is the 2018 Kia Optima Phev a good car?
That is a low number of complaints for a car on sale this long. So far owners have filed 8 complaints with NHTSA.
What is the most common problem with the 2018 Kia Optima Phev?
The engine & cooling — 4 complaints, 50% of all complaints for this model year. Next are the electrical system (3) and windows, wipers & sunroof (1).
How many recalls does the 2018 Kia Optima Phev have?
There are 2 recalls for the 2018 Kia Optima Phev, the most recent from August 24, 2023 (latch). Recall repairs are free at any authorized dealer — check whether yours has been done with the VIN recall check.
At what mileage do 2018 Kia Optima Phev problems happen?
The median mileage reported in complaints is about 19,000 miles; 100% of problems with a recorded mileage started before 50,000 miles.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.