2018 Kia Optima Problems and Top Complaints – Is Your Car A Lemon?

Updated on April 30th, 2023 Author: Brian Jones

Consumers hoping to find a quality mid-size car are often drawn to the style of the 2018 Kia Optima. It has a sleek design and is hailed as a reliable option. Even the automaker claims that the new models are “driven to stand out.” Research shows that this model does stand out, but not for the reasons most expect. Instead, it is riddled with engine troubles, powertrain malfunctions and the possibility of an accident.

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NHTSA Complaints for the 2018 Kia Optima

Problems with the Engine

With a properly functioning engine, a vehicle feels comfortable to drive and has the power needed to get anywhere in style. Sadly, that’s not the case with the 2018 Kia Optima.

One NHTSA complaint states, “On 3/29/19 was traveling to work. On Interstate 53 Southbound car went to limp mode. No power. Managed to get to dealership. They tried to repair my vehicle for 1 month after they told me that the engine need to be replaced they managed to change wiring harness. After  month it was done. I took car back. 1 or 2 weeks later car went into limp mode again with same problem. Filed a claim with Kia and BBB to resolve it. As of right now they had inspections on my vehicle as they stated from Kia California HQ and from Kore HQ with no luck to repair it. As manager told me they don’t have any ideas how to fix it. Want Kia to buyback my vehicle and let me get away from this lease with reimbursement on payments because car no in my possession for 128 days and counting. They switched me 3 loaners.”

It turns out that Kia is dealing with numerous engine issues on the Optima. With Service Bulletin #VPI1802_DP, we see the company discussing ways to protect the engine from excessive rod bearing damage. This shouldn’t even be a concern on a new vehicle, yet Kia is scrambling to figure out ways to fix it. If this model is the poster child for standing out, it might be better to hide in a corner instead.

Here are some actual complaints logged with the NHTSA about the 2018 Kia Optima Engine Problems:

TL* THE CONTACT OWNS A 2018 KIA OPTIMA. WHILE DRIVING 20 MPH, THE CONTACT WAS NOTIFIED BY OTHER MOTORISTS THAT FLAMES WERE PRESENT UNDER THE VEHICLE. THE VEHICLE WAS PULLED OVER TO THE SIDE OF THE ROAD AND SMOKE APPEARED UNDER THE HOOD. THE CONTACT AND A PEDESTRIAN EXTINGUISHED THE FIRE. THE FIRE AND POLICE DEPARTMENTS WERE AT THE SCENE, BUT THE CONTACT WAS UNSURE IF REPORTS WERE FILED. THERE WERE NO INJURIES. THE VEHICLE WAS TOWED TO NORTHSTAR KIA WHERE THE CONTACT WAS INFORMED THAT THERE WAS AN ENGINE FIRE. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS MADE AWARE OF THE FAILURE. THE FAILURE MILEAGE WAS 22,000.

Problems with the Transmission

What’s most disappointing is the 2018 Kia Optima also struggles with transmission trouble. Between the engine and transmission, it’s amazing that owners can get anywhere behind the wheel of this car.

Just look at this NHTSA complaint. “Transmission failed after 4 months and 3,800 miles while driving local streets. Kia dealers refused to repair under warranty.”

What could the owner possibly have done to the transmission within 4,000 miles that would cause the transmission to go bad and void the warranty? It’s just another case of Kia not living up to their promises. Another example of transmission trouble with this model is illustrated with Service Bulletin #TSBENG177. It states that the ECU and TCU require updates to repair shift quality concerns and extended crank conditions. In fact, the company talks about these complaints throughout several bulletins as they attempt to figure it all out. If Kia wants this vehicle to stand out, it first needs to be able to be driven on the road.

Here are some actual complaints logged with the NHTSA about the 2018 Kia Optima Powertrain Problems:

TRANSMISSION FAILED AFTER 4 MONTHS AND 3800 MILES WHILE DRIVING ST LOCAL STREETS, KIA DEALERS REFUSED TO REPAIR UNDER WARRANTY.

THE CV AXLE ASSEMBLIES SNAP LIKE THE 2016 MODELS DO KIA’S RECALL NUMBER SC139.

Problems with the Electrical System

With the electrical system, it’s evident that there are just as many problems. It appears that Kia just can’t seem to get it working correctly.

Just look at this complaint filed by the NHTSA. “The contact owns a 2018 Kia Optima. While reversing the vehicle, the rear and side sensors failed to identify two people walking past. There were no warning indicators illuminated. The vehicle was taken to [dealer] who stated that the sensors were working as designed. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The failure mileage was 14,356.”

While this is a scary situation, imagine the concern over an electrical issue with the hybrid models. In fact, the NHTSA issued a recall because the voltage protection device might activate. NHTSA Campaign Number 18V161000 states that the VPD might enable during operation of EV mode, which might lead to a loss of power and increased chance of an accident. To repair the problem, Kia must remove the switch and install two new Battery Management Systems with Overvoltage Protection Devices.

For review, we’ve seen plenty of ways that the Optima stands out, as intended by the automaker. It fails to drive at all when the engine fails, contains a defective transmission and refuses to alert drivers when people walk behind it. With all of these issues and the countless others on the Internet, it’s clear to see that this vehicle has gotten a lot of attention, but only for negative reasons.

Here are some actual complaints logged with the NHTSA about the 2018 Kia Optima Electrical Problems:

PURCHASED A BRAND NEW 2018 KIA OPTIMA . NEVER REALLY HAD ANY ISSUES WITH IT UNTIL FRI NOV 22. AS I WAS LEAVING FROM WORK MY CAR DID A VERY ABRUPT JERK THAT I ACKNOWLEDGED BUT DIDN?T THINK ANYTHING OF IT BECAUSE MY GAS LIGHT HAD JUST CAME ON. BUT TODAY WHICH IS SUNDAY MY CAR?S EPS (ELECTRIC POWER STEERING) LIGHT FLASHED. WEIRDED OUT I LOOK AT THE MANUAL IN THE GLOVE COMPARTMENT. AS I EASED INTO MY APARTMENT COMPLEX THE CAR DID THAT SAME JERK, THE STEERING WHEEL WENT HARD TO MANAGE/STEER AND 6 OTHER LIGHTS STARTED BLINKING( PARKING BREAK LIGHT, EPB LIGHT , ABS LIGHT,ESC LIGHT ,BATTERY CHARGE LIGHT, AND THE MASTER MALFUNCTION LIGHT) . I COULD NO LONGER MANIPULATE MY WHEEL SO I PULL FORWARD ONTO A OPEN SPOT AND PUT IT IN PARK. THE MOMENT I DID THIS THE CAR CUT OFF. IT WILL NOT TURN OVER, IT WILL NOT DO ANYTHING BESIDES TICK. I HAVE BEEN GREAT WITH MAINTENANCE BECAUSE IT WAS EITHER FREE OR DIRT CHEAP SO I ALWAYS TOOK IT TO THE DEALERSHIP. I HAVE READ MORE REVIEWS OF PEOPLE GOING THROUGH SIMILAR THINGS. JUST IMAGINE IF I HAD MY CHILD IN THE CAR, ON THE INTERSTATE AND COULD NO LONGER CONTROL MY STEERING WHEEL OR THE CAR JUST DYING MID DRIVE ON THE INTERSTATE HOW DANGEROUS THIS ISSUE IS. MY CAR IS BASICALLY 3 YEARS OLD AND HAS LESS THAT 50 K. IT HAS NEVER BEEN WRECKED , TOWED OR DAMAGED STILL PRACTICALLY NEW. I HAVE ALSO READ SIMILAR RECALLS ABOUT ELECTRONIC ISSUES THAT ARE ONLY RELEVANT TO THE HYBRIDS . THE RECALL SEEMS SIMILAR.

Your Lemon Law Legal Rights

Think you have a lemon? Sit back and let the experts work out your lemon case at no cost to you. The law makes Kia pay legal fees. You may be able to get your lemon out of your life. Every year, auto manufacturers buy back, replace or pay cash settlements to thousands of ‘lemon’ owners like you.

About the Author:

Brian Jones spent more than 30 years working as an ASE Certified Master Tech and Parts Specialist at multiple dealerships. Brian has become an authority in the industry, traveling across the country to consult for car dealerships and contributing his expertise as a writer for several major automotive publications. In his spare time, Brian enjoys working on pickup trucks, muscle cars, Jeeps and anything related to motorsports.

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