What 252 owners told NHTSA about the 2017 Kia Optima

I just bought this car and it runs thru oil fast.

NHTSA ODI 11746667

Loosing oil putting oil in every 3 to 4 days no leaks on ground or oil pan or drain plug.oil don't smell or looks burnt happened around did 2 oil changes in a week still the same. Car will sputer hesitation on acceleration every so often

NHTSA ODI 11741793

The engine of this vehicle is still exhibiting the issues that are under the class action lawsuit. Engine. Was not repaired properly by dealership. I must change my oil around 1700 miles

NHTSA ODI 11740357

The contact owns a 2017 Kia Optima. The contact stated that on three of four occasions while driving at approximately 50 MPH, the vehicle began rattling and shaking, and he observed a knocking noise emanating from the engine compartment. The check engine warning light illuminated. The vehicle was taken to a dealer where it was diagnosed that the knock sensor needed to be replaced, and he was advised that his vehicle may have been included in Manufacturer Recall Number: SC162. The vehicle was not repaired. The manufacturer was notified of the failure and a complaint was filed. The failure mileage was approximately 98,000.

NHTSA ODI 11740090

Constant Mis-firing, must put oil in car every 3 to 4 weeks. Hesitation when driving and sputtering.

NHTSA ODI 11735036

On March 23, 2026, I took my 2017 Kia Optima Plug-In Hybrid (VIN: [XXX] ) to Mark Kia [XXX] ) solely for two open safety recalls: SC218 (Engine Inspection/Replacement and KSDS software installation) and SC278 (Emergency Trunk Latch Release) under Repair Order #6807251. No customer-pay work was performed. The Multi-Point Inspection that day noted only the cabin air filter. During the drive home on March 23, a faint rotten-egg (H₂S) smell appeared for the first time. By the morning of March 24, 2026, the smell was severe. I immediately returned the vehicle. Under new Repair Order #6807360, a second Multi-Point Inspection suddenly recommended $1,134.10 in customer-pay services (new 12V battery, fuel induction service, cooling system service, brake fluid exchange, and ATF exchange) that were not flagged the previous day. Since the recall service, the vehicle has developed numerous new defects that never existed before: Rotten-egg smell (H₂S) Intermittent AC that blows warm in stop-and-go traffic Passenger-rear power window clicks but will not roll down Brake warning (“Stop vehicle and check brakes”) “Key not detected” message Passenger-side mirror pushed in with temporary motor malfunction 12V battery cover left completely disassembled and misplaced in the trunk Complete no-start / dead 12V battery condition (will not crank even after multiple jump attempts as of March 30, 2026) On March 24, 2026, I sent a formal demand letter by certified mail (received and signed for by the dealership on March 27, 2026) giving Mark Kia five business days (until close of business March 31, 2026) to provide a free tow, free loaner, and free repair of all defects. I followed up with six supplemental addendums (dated March 24–30, 2026) attaching photos and videos of every issue. On April 1, 2026, Service Director [XXX] replied by email and admitted in writing (twice) that the dealership did not follow recall procedure INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI 11728774

Engine issues started the third month after sales. Jerking, shaking, declining performance, metal clicking noise, loss of power while driving. Kia has been working on the car for a year.

NHTSA ODI 11726667

The contact owns a 2017 Kia Optima. The contact stated that while driving at 67 MPH, the vehicle experienced a loss of drive power, and the vehicle went into LIMP Mode. The check engine and HEV warning lights were intermittently illuminated. The contact entered the vehicle settings, and the ECU message was displayed. The contact stated that the failure had occurred three times. The vehicle was taken to the dealer, but the failure could not be duplicated. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 130,000.

NHTSA ODI 11717534

“My vehicle, a 2017 Kia Optima, had repeated safety issues documented in service records. Despite multiple repair attempts (per attached records), the problem remained unresolved and put my safety at risk. I’m seeking further investigation or resolution.”

NHTSA ODI 11716078

My fiancée and I just recently bought this car with the 1.6T-GDi engine I immediately replaced the oil even though the dealership said that he just replaced it. I put 7 quarts of oil topping off from awk consumption after I initially changed the oil filter. Those 7 quarts were added over the period of three weeks and it’s just progressively gotten worse. I’m putting a quart to 1.5 quarts of oil in here every other day. Worried about it causing total failure & being at risk of being stranded with 2 kids due to the only engine I’ve been able to find that Kia doesn’t have any recall touched base on is the GAMMA 1.6 engine. The turbo GAMMA 1.6. The N/a 1.6 was covered but it has ungodly pop/clunking backfiring sound coming from either intake manifold or valve train please help. Times are hard enough as it is to be without a vehicle due to a fault other than none of my own the dealership extended powertrain warranty isn’t being honored by Kia even though they said it would just don’t want something to happen to me or the car that’s beyond my capabilities and knowledge and ultimately result in my spouse not having a reliable and/or safe means of transportation to/from work and commuting kids as well. Thanks in advance

NHTSA ODI 11715807

unknown

NHTSA ODI 11715900

The vehicle is consuming excessive amounts of oil. The dipstick was completely dry before 5000 miles were up. I had to add some oil to the engine to avoid engine failure. I have reported this to Jim Ellis dealership in Kennesaw GA but I was told to drive the vehicle until it knocks or the knock sensor goes.

NHTSA ODI 11711382

The engine in my 2017 Kia Optima (VIN: [XXX] ) seized and locked up, a known defect associated with Kia’s Theta II 2.4L GDI engines. When I contacted Kia regarding engine replacement, I was told coverage would not apply because a required KSDS ECU update recall was not completed. During multiple phone calls with Kia Customer Care, Kia admitted that they did not have my contact information on file and added it during my call. Because Kia did not have my information, I never received any recall notification and was denied the opportunity to comply with the KSDS update. Kia has also provided conflicting information regarding whether recalls were open on my VIN while still relying on recall completion status to deny coverage. I believe Kia failed to properly notify me of a safety recall and is unfairly denying coverage for a known engine defect. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI 11708746

Kia Engine Settlement-Kia America and Grand Forks KIA dealership is refusing a mandatory diagnostic test for excessive oil consumption under the Kia Theta II Engine Class Settlement, despite the vehicle having the required KSDS software update installed. The vehicle is consuming 1 quart of oil every 1000 miles, requiring constant topping off to prevent engine seizure. Vehicle was brought to Kia Grand Forks on 7/21/25 was told that the valve gasket needed to be changed. Engine light illuminated 10/2025 and car was unable to make it back to dealership from 58369. Vehicle was brought to local mechanic where I was told that the has failed and that the spark plugs had oil on them. Mechanic changed the spark plugs to make it to Grand Forks Kia on 10/14/25 I was told that the Turbo needed to be replaced for $3300 before they can do an oil consumption test. There were no issues with the turbo before it was driven to Grand Forks on 10/14/25. Kia America refuses to cover the engine warranty which will lead to "sudden engine stall, loss of power, or vehicle fire," which are primary safety concerns monitored by NHTSA.

NHTSA ODI 11708673

The contact called on behalf of her daughter who owns a 2017 Kia Optima. The contact stated while driving at approximately 60 MPH, the vehicle made an abnormal knocking sound, the cruise control was inoperative, the infotainment screen darkened, and the charging outlet was inoperative. The Check Engine warning light was intermittently illuminated. The vehicle was taken to the contact's residence, and the contact used a vehicle scanner to scan the vehicle. The contact stated that DTC: P1326 for the Knock Sensor Detection System (KSDS) was found, which detected excessive engine vibration. A dealer was contacted; however, the vehicle was not diagnosed or repaired by the dealer. No further information was available. The failure mileage was approximately 98,000.

NHTSA ODI 11707896

Vehicle experiences sudden and dangerous loss of power while driving, including hesitation during acceleration, consistent with connecting-rod bearing failure risk known in this model’s GDI engine. Dealer estimate found timing and oil-flow component failures connected to internal engine damage. Vehicle is unsafe to drive and stalls/lacks power unexpectedly, creating a high risk of crash.”

NHTSA ODI 11704089

I own a 2017 Kia Optima with a major internal engine defect. Starting shortly after purchase, the car lost power and consumed fuel unusually quickly. Over time, the engine began burning excessive oil and now produces a loud knocking sound (bearing knock), indicating internal bearing failure. These symptoms are consistent with known Kia engine defects (bearing wear / piston ring failure). The defect is a serious safety concern: because of weak bearings and high oil consumption, the engine could stall, seize, or catch fire. The dealership has refused to repair or replace the engine. I am reporting this as a safety defect and request NHTSA investigation.

NHTSA ODI 11699628

I purchased the 2017 Optima Hybrid from Huntington Beach Hyundai on [XXX]. I made sure to double check with the dealer if the engine and hybrid battery were in good condition, in which the salesman reassured me everything is good. The car was driving okay for a while, and I had oil change and tires/alignment changed recently. Just barely 4 months in after I owned the car, the incident happened on the night of [XXX]. I was driving on the highway near the Getty going roughly 70 mph up the mountain roads while all of a sudden the "check hybrid system" warning came on in the car. The car immediately went into limp mode, and I did everything I could to slow the car to a complete stop, and stop on the freeway shoulder safely. It was a traumatizing experience to me, as this is a major safety issue with the vehicle, and other cars were travelling really fast in LA mountain areas. I had the car towed to a auto repair shop the next day, the mechanics did a deep inspection and informed me the hybrid inverter has failed. I paid $2,177 to replace the hybrid inverter with the mechanic. The mechanic also informed me while they were test driving they heard a knocking sound from the engine. I did a look up and found out there is a class settlement and safety campaigns on the engine for 2017 Optima Hybrid due to the faulty factory rod bearings, and the 150K miles extended warranty from Kia should apply to replace my faulty engine free of charge. I will be getting my car towed to Car Pros Kia in Huntington Beach on October 15th, 2025, and request the dealer to replace my engine per Kia's extended warranty. I am filing the complaint because the car is having problems after problems in barely 4 months of ownership, in which I believe I have purchased a lemon, or Huntington Beach Hyundai knowingly hid the facts the components were faulty. I have also filed a case with Kia corporate. Attached is the repair invoice for the hybrid inverter. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI 11693506

Engine is consuming a large amount of oil. Oil is gunking up spark plugs causing them to be replaced every 10-12 months. Have to add oil 3-5 times per month. This is our 2nd Kia optima and the first (2011) with seized engine in which Kia paid for replacement.

NHTSA ODI 11692431

Oil is burning too fast... Car has had an issue like this in the past and the problem resulted in a blown engine... Re-call was found by dealer and honored and endinge re-placed.. Car is now expierenceing this problem again... Second, steering wheel is locking when turnning fully left... Third, car smells extremely strong like gasoline when car is warming up...

NHTSA ODI 11690860

Engine completely shut down when driving it. Had it replaced among many other things then found out it was part of a class action lawsuit. I have spent two years trying to recoup the money I lost in repairs and the cash I paid for the car.

NHTSA ODI 11686675

for the past year, I have been constantly replacing the spark plugs and ignition coil in my 2017 Kia optima. Recently I have had the valve cover gasket replaced. It is a constant oil consumption issue. I have received the P1326 diagnostic code. My dealership told me that the engine cannot be replaced unless it’s knocking. This is my only mode of transportation, and I would hate for me to be stranded because I’m waiting for the engine to knock for my engine to be replaced.

NHTSA ODI 11684750

Car began hesitating and stalling, particularly from a stop. Engine light came on. Took the car to the KIA dealership for diagnosis. Was told by svc coordinator that the diagnosis indicated a bad knock sensor. The technician replaced the knock sensor, then test drove the car. It failed immediately. I was told that it would likely need engine replacement. After a few days, svc coordinator called and said that KIA recommended replacing the knock sensor (again) and perform a tuneup. They declined to replace the engine. The car runs in "limp home mode" (Kia's terminology), hesitates and stalls so as to make it very unsafe to operate. The engine on this car was replaced about two years ago for excessive oil consumption. There cannot be more than 30k miles on the new engine. KIA stated that there is a lifetime warranty on the replaced engines, but are apparently not going to honor the warranty. Car is serviced regularly and is in otherwise excellent condition.

NHTSA ODI 11682175

My car is burning oil and oil is covering my spark plugs. Was mentioned about decarbonizing

NHTSA ODI 11681530

--- **Summary of Complaint – 2017 Kia Optima** My 2017 Kia Optima (VIN: [XXX] ) experienced sudden engine failure due to a damaged piston. There were no warning signs—no knock codes or dashboard alerts—prior to the malfunction. Despite regular maintenance and timely oil changes, Kia denied warranty coverage, leaving me with significant repair costs. This issue appears consistent with reported engine problems in similar Kia models and could represent a broader manufacturing defect. I'm submitting this report in hopes of prompting an investigation into a potential safety hazard. A recall may be necessary to prevent similar failures and protect INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI 11678127