FaultScore

FaultScore report

2018 KIA Optima Phev problems

Owners have filed 12 complaints about the 2018 KIA Optima Phev with NHTSA between 2018 and 2025. The largest single group is the engine & cooling.

Not graded

Too few complaints, or too short a model run, to compare fairly.

How this is worked out

The numbers

12

Complaints

0

Crashes reported

0

Fires reported

0

Injuries reported

19,000 mi

Median mileage at failure

Half of reported failures happened before this

100%

Failed under 36,000 miles

Inside a typical bumper-to-bumper warranty

How 2018 compares with every other KIA Optima Phev

Click any bar to open that year's report.

Complaints filed with NHTSA, by model year. Bar colour is the FaultScore grade: A B C D F ungraded

What breaks on a 2018 KIA Optima Phev

Every complaint is filed against a part. Follow any row for the complaints about that part alone.

Engine & Cooling 4 33.3%

Median failure at 19,000 miles

Electrical System 3 25.0%

Median failure at 19,000 miles

Other & Unspecified 2 16.7%

Median failure at 18,800 miles

Windows, Mirrors & Wipers 1 8.3%

Median failure at 7,500 miles

Steering 1 8.3%
Transmission & Drivetrain 1 8.3%

Median failure at 19,000 miles

When it fails

Odometer readings owners gave when they filed. About half of all complaints include one.

1,000 – 9,999 miles 1 10.0%
10,000 – 24,999 miles 8 80.0%
25,000 – 49,999 miles 1 10.0%

When owners complained

A spike years after the car went on sale usually means a part wearing out on schedule across the whole fleet — the kind of pattern no single owner can see from inside their own car.

Sep 2018 peak 6 Jul 2025

NHTSA investigations into the 2018 KIA Optima Phev

An investigation is the step before a recall: the agency has seen enough complaints to look into a pattern itself. An open one means it thinks something may be wrong and nothing has been fixed yet.

DP22005 Opened 27 Jan 2023 Closed 7 Aug 2023 ELECTRICAL SYSTEM:PROPULSION SYSTEM

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. The standard applies to hybrid and electric vehicles that have a gross vehicle weight rating of 4,536 KG or less or are defined as low-speed vehicles. The standard became fully applicable to all such vehicles manufactured on or after Marc...

DP22003 Opened 12 Sep 2022 Closed 12 Dec 2023 ENGINE

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. The Petitioners cited examples of complaints indicating that the subject vehicles were experiencing rapid loss of engine oil due to oil drain plug back outs, resulting in loss of motive power and/or catastrophic engine damage. Additional complain...

EA21003 Opened 22 Dec 2021 Closed 5 Feb 2024 ENGINE

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.  During the PE investigations, Hyundai and Kia issued several recalls to address vehicle fires, including those due to engine failures involving various engine types.  The remedies for the engine failure recalls typically involve engine inspection (to detect existing damage), and if necessary, engine...

The most recent complaints

In the owners' own words, exactly as filed with NHTSA.

at 35,000 miles Yucaipa, CA

ELECTRICAL SYSTEM:12V/24V/48V BATTERY

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. The manufacturer was not made aware of the failure. The approximate failure mileage was 35,000.

NHTSA complaint #11675096 — an unverified report by a vehicle owner.

Alpine, CA

STEERING

The plastic coupling for the steering is broken in my 2018 Kia optima the same Issue that the 2011-2014 issue optima’s have my car has this same issue.

NHTSA complaint #11660146 — an unverified report by a vehicle owner.

Redlands, CA

ENGINE AND ENGINE COOLING

See attached document for complaint.

NHTSA complaint #11609737 — an unverified report by a vehicle owner.

at 19,000 miles Sacramento, CA

POWER TRAIN

I WAS TOLD BY THE DEALERSHIP THAT MY 2018 KIA OPTIMA PHEV WAS REPAIRED BUT AFTER I DROVE IT OFF THE LOT AND GOT ON THE FREEWAY THE WARNING LIGHT CAME ON AGAIN AND LOST ALL POWER. I ALMOST GOT INTO ANOTHER ACCIDENT BECAUSE OF THIS. THE DEALERSHIP SAID THEY WORKED WITH KIA TECHNICAL SUPPORT TO FIX MY CAR BUT APPARENTLY KIA DOESN'T KNOW WHAT'S WRONG WITH THEIR OWN CAR. THE VEHICLE HAS ONLY 19K MILES. I'M AFRAID FOR MY SAFETY AND MY FAMILIES THAT THIS WILL CONTINUE TO HAPPEN.

NHTSA complaint #11398068 — an unverified report by a vehicle owner.

at 19,000 miles Sacramento, CA

ELECTRICAL SYSTEM

I WAS TOLD BY THE DEALERSHIP THAT MY 2018 KIA OPTIMA PHEV WAS REPAIRED BUT AFTER I DROVE IT OFF THE LOT AND GOT ON THE FREEWAY THE WARNING LIGHT CAME ON AGAIN AND LOST ALL POWER. I ALMOST GOT INTO ANOTHER ACCIDENT BECAUSE OF THIS. THE DEALERSHIP SAID THEY WORKED WITH KIA TECHNICAL SUPPORT TO FIX MY CAR BUT APPARENTLY KIA DOESN'T KNOW WHAT'S WRONG WITH THEIR OWN CAR. THE VEHICLE HAS ONLY 19K MILES. I'M AFRAID FOR MY SAFETY AND MY FAMILIES THAT THIS WILL CONTINUE TO HAPPEN.

NHTSA complaint #11398068 — an unverified report by a vehicle owner.

at 19,000 miles Sacramento, CA

ENGINE

I WAS TOLD BY THE DEALERSHIP THAT MY 2018 KIA OPTIMA PHEV WAS REPAIRED BUT AFTER I DROVE IT OFF THE LOT AND GOT ON THE FREEWAY THE WARNING LIGHT CAME ON AGAIN AND LOST ALL POWER. I ALMOST GOT INTO ANOTHER ACCIDENT BECAUSE OF THIS. THE DEALERSHIP SAID THEY WORKED WITH KIA TECHNICAL SUPPORT TO FIX MY CAR BUT APPARENTLY KIA DOESN'T KNOW WHAT'S WRONG WITH THEIR OWN CAR. THE VEHICLE HAS ONLY 19K MILES. I'M AFRAID FOR MY SAFETY AND MY FAMILIES THAT THIS WILL CONTINUE TO HAPPEN.

NHTSA complaint #11398068 — an unverified report by a vehicle owner.

at 19,000 miles Sacramento, CA

UNKNOWN OR OTHER

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. I'M AFRAID THAT IF I TAKE THE CAR TO THE DEALERSHIP THAT THEY WONT BE ABLE TO REPLICATE THIS ISSUE SINCE THE WARNING LIGHTS ARE NO LONGER ON AND THEY TELL ME THEY CANT FIND THE ISSUE AND THIS HAPPENS AGAIN IN THE FUTURE. THERE ARE SEVERAL FORUMS WHERE PEOPLE HAVE THIS SAME ISSUE FROM 2014 HYBRID MODELS AND UP AND HAS HAPPENED TO THEM NUMEROUS TIMES AND THE DEALERSHIP TELLS THEM THEY CANT DUPLICATE THE PROBLEM.

NHTSA complaint #11396321 — an unverified report by a vehicle owner.

at 19,000 miles Sacramento, CA

ELECTRICAL SYSTEM

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. I'M AFRAID THAT IF I TAKE THE CAR TO THE DEALERSHIP THAT THEY WONT BE ABLE TO REPLICATE THIS ISSUE SINCE THE WARNING LIGHTS ARE NO LONGER ON AND THEY TELL ME THEY CANT FIND THE ISSUE AND THIS HAPPENS AGAIN IN THE FUTURE. THERE ARE SEVERAL FORUMS WHERE PEOPLE HAVE THIS SAME ISSUE FROM 2014 HYBRID MODELS AND UP AND HAS HAPPENED TO THEM NUMEROUS TIMES AND THE DEALERSHIP TELLS THEM THEY CANT DUPLICATE THE PROBLEM.

NHTSA complaint #11396321 — an unverified report by a vehicle owner.

at 19,000 miles Sacramento, CA

ENGINE

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. I'M AFRAID THAT IF I TAKE THE CAR TO THE DEALERSHIP THAT THEY WONT BE ABLE TO REPLICATE THIS ISSUE SINCE THE WARNING LIGHTS ARE NO LONGER ON AND THEY TELL ME THEY CANT FIND THE ISSUE AND THIS HAPPENS AGAIN IN THE FUTURE. THERE ARE SEVERAL FORUMS WHERE PEOPLE HAVE THIS SAME ISSUE FROM 2014 HYBRID MODELS AND UP AND HAS HAPPENED TO THEM NUMEROUS TIMES AND THE DEALERSHIP TELLS THEM THEY CANT DUPLICATE THE PROBLEM.

NHTSA complaint #11396321 — an unverified report by a vehicle owner.

at 18,600 miles Delray Beach, FL

UNKNOWN OR OTHER

I LEASED A NEW #KIA #OPTIMA #PHEV FROM YOU IN JULY OF 2018. IN JULY OF 2020, THE CHARGING CABLE LODGED IN THE CAR AND IT TOOK 4 HOURS FOR ROADSIDE ASSISTANCE TO REMOVE IT. ON DECEMBER 2, 2020, I GOT A CHECK ENGINE LIGHT AND MADE AN APPOINTMENT FOR SERVICE, BUT BEFORE I COULD BRING IT ON DEC 3, THE CHECK ENGINE LIGHT BECAME A TURN ENGINE OFF NOW LIGHT, AND THE CAR STOPPED DEAD IN THE MIDDLE OF A BUSY HIGHWAY WITH A WISP OF SMOKE FROM UNDER THE HOOD, A DANGEROUS SITUATION. I HAD IT TOWED TO KIA OF DELRAY. IT'S STILL THERE, THEY HAVEN'T TOLD ME WHAT'S WRONG. IT IS 2.5 YEARS OLD WITH JUST OVER 18K MILES ON IT. I LEASED THE CAR WHEN I LIVED IN CA, AND NOW LIVE IN FL, WHICH IS ALSO A PROBLEM, AS THE DEALERSHIP HERE JUST DOESN'T SEEM EQUIPPED TO SERVICE A PHEV. THE LEASE IS SCHEDULED TO END IN JULY 2021 BUT THE MANUFACTURER HAS REFUSED TO OFFER ME AN OPTION TO RETURN THE CAR EARLY, YET IT FEELS UNSAFE TO CONTINUE TO DRIVE IT (AND IT'S NOT OPERATIONAL RIGHT NOW).

NHTSA complaint #11384136 — an unverified report by a vehicle owner.

at 11,000 miles SAN Jose, CA

ENGINE

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.

NHTSA complaint #11219554 — an unverified report by a vehicle owner.

at 7,500 miles Compton, CA

VISIBILITY/WIPER

THE CAR WAS PARK IN THE HOUSE AND WHEN I GET BACK I SAW A LONG CRACK ON THE WINDSHIELD SO I CHECK THE SURROUNDING IF THERE IS SOMETHING FELL ON IT BUT THERE'S NO EVEN AN IMPACT ON IT IT'S JUST CRACK FROM THE TOP OF THE WINDSHIELD UP TO THE MIDDLE CENTER. IT'S A BRAND NEW CAR SO HOW WILL THE WINDSHIELD GET CRACK LIKE THAT. I ASK AROUND TO REPLACE MY WINDSHIELD AND MOST OF THEM TOLD ME THAT IS A COMMON PROBLEM WITH THE NEW VEHICLE LIKE MINE AND THEY EVEN ASK THE DEALER IF IT'S AVAILABLE AND THEY SAID IT WILL TAKE ABOUT A MONTH TO HAVE IT.

NHTSA complaint #11131603 — an unverified report by a vehicle owner.