UNKNOWN, Engine excessively burns oil and is now seized. Kia used the same engine in this car as they did in the 2016-19 Models which were recalled for engine failure, however mine was not included. 2.4 Theda Engine.
NHTSA ODI 11660698
Home · 2020 Kia Optima · Complaints
These are the actual owner complaints behind this car’s reliability verdict, filed with the federal government, unedited. They’re unverified reports, not confirmed defects: read them as leads for your pre-purchase inspection, not a diagnosis.
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UNKNOWN, Engine excessively burns oil and is now seized. Kia used the same engine in this car as they did in the 2016-19 Models which were recalled for engine failure, however mine was not included. 2.4 Theda Engine.
NHTSA ODI 11660698
I was driving down the interstate and all of a sudden the blinking lights of the check engine light came on and automatically I went from 75 mph down to 63 mph and when I looked up what it was, it was the knock detection system of the 2020 Kia Optima. I could not accelerate beyond 63 mph and I fear that the engine might stall on me so I went to O’Reillys and have them check it and it says it’s the P1326 Code
NHTSA ODI 11658199
The car drives slowly and sputters because oil is burning out quickly. I have to replenish oil continuously.
NHTSA ODI 11657548
Accelerating at a normal rate to get on the highway and the check engine light starts flashing out of nowhere and car goes into limp mode. Made it to local shop and they informed me it was a P1326 code and that a knock sensor would have to be replaced, but that Kia has recalled the older models for this same reason.
NHTSA ODI 11653605
Hi, thank you for taking the time to look over my complaint. On Saturday march 22 while driving down the highway going about 75 mph, my car died. The check engine light was flashing and so was the oil light. I pulled over to the shoulder and when I tried cranking the car it sounded like a rumming noise and the car would not stay on. I had the vehicle towed to Texas Star Auto Shop. On monday march 24th i spoke with the mechanic and he said there is an internal engine problem . Since I am a 2nd owner and the car has 105,736 miles kia will not honor their extended warranty and I am left to pay out of pocket for repairs est cost 10,000+. I am now without a reliable transportation. This has left me annoyed and unhappy with the assistance from Kia.
NHTSA ODI 11651623
Dealing with sudden excessive oil consumption at 130,000 miles. Had an oil change about 2,000 miles ago and oil sensor has been going off after 1,500-2,000 miles driven. Mechanic put 3 more quarts in and a week and a half later oil sensor is going off again indicating low oil. Mechanic confined this has been a frequent problem with this engine and insists piston rings are faulty & will eventually need engine replacement.
NHTSA ODI 11651035
The contact owns a 2020 Kia Optima. The contact stated that while attempting to make a right turn, there was an abnormal sound coming from the rear driver’s side window. The contact discovered that the glass had shattered. The contact stated that the Police Department advised her to contact the dealer where the vehicle was purchased, not the Insurance Company. The contact was informed that the failure was caused by a manufacturing defect. A police report was filed. The vehicle was not taken to the dealer or an independent mechanic to be inspected or repaired. diagnoses. The manufacturer was not notified of the failure. The approximate failure mileage was 58,009.
NHTSA ODI 11650912
Same issue as the 2011-2019 recalled vehicles. (P1326)
NHTSA ODI 11647960
I am filing this complaint due to severe and ongoing safety defects in my 2020 Kia Optima EX, which has repeatedly stalled while driving, creating a life-threatening road hazard. Since September 2024, my vehicle has suffered from major failures, including a complete transmission replacement, multiple high-pressure fuel pump replacements, multiple oil flushes due to fuel contamination, and all fuel injectors replaced. Despite all of these “repairs” performed by a Kia-authorized dealership, the check engine light continues to return, and the vehicle still stalls unexpectedly, making it dangerous to drive. On March 10, 2025, after Kia claimed to have tested the vehicle for 200 miles, I picked up the car from the dealership, only for it to stall and trigger the check engine light within hours before I even reached my destination. This vehicle has been returned to me multiple times in an unsafe condition. Additionally, an independent mechanic discovered an engine oil leak and a torn axle that Kia’s dealership never disclosed. This raises major concerns about their lack of proper inspection and repair procedures. This is a serious safety issue that Kia refuses to take accountability for. I request an immediate investigation into this matter before this defect leads to an accident.
NHTSA ODI 11647773
Oil consumption has rapidly been increasing causing the loss of several quarts of oil. Inspection by service center confirmed this is a known Kia issue and recommended a flush to help combat some of the issue. Service center did note that this issue would not fix the problem, but put off needing to replace the engine. Oil light was not flashing on the dash unless coming to a quick stop, but then would disappear. The value of these cars has resulted in quite a bit of negative equity for folks due to the theft issue. Now add on a fear of blowing an engine cause your vehicle is burning through oil like no tomorrow.
NHTSA ODI 11646384
My car is using a lot of oil and I have to change the oil every 2 thousand miles, oil light will come on and I check the oil and it shows the oil stick almost dry within 2,000 miles after having oil changed. The car will loose power and has a ticking noise in the motor. It’s frustrating to have to change the oil every 2,000 miles instead of every 3,000-5,000 miles like most vehicles.
NHTSA ODI 11645212
The contact owns a 2020 Kia Optima. The contact stated while operating the vehicle, there was an abnormal rattling sound coming from the engine compartment. The contact stated that the vehicle was hesitating and there was excessive oil consumption. The vehicle was taken to the local mechanic who diagnosed the vehicle and determined that the piston rings were faulty, and the engine needed to be replaced. The vehicle was not yet repaired. The local dealer was notified of the failure, but no assistance was offered. The manufacturer was contacted. The failure mileage was 127,000.
NHTSA ODI 11645355
Vehicle Check engine light started flashing on and off, Code thrown is a P1326 and vehicle went into limp mode, shutting down power essentially going down the highway. Oil burning is excessive, and replacement of oil is at 1-2 quarts every 2 weeks. Engine is not running smoothly. No warning signs of oil burn present until oil pressure light flickers on when taking a curve or sitting on a major incline. Kia Dealership is aware of an issue with the P1326 codes and bearing wear, however, year of vehicle seems to not be included in the original lawsuit and recall/safety notice from all indications. Engine was manufactured and is the same as the 2019 engine that is included. Engine seizure is potential at highway speeds which could cause major harm or death during travel without warning.
NHTSA ODI 11644708
The contact owns a 2020 Kia Optima. The contact stated while driving at an undisclosed speed, the check engine warning light illuminated. The vehicle was taken to an independent mechanic, and the vehicle was connected to a diagnostic machine. The DTC indicated a glow relay failure. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 118,000.
NHTSA ODI 11643407
Code P1326 and oil pressure light keeps flashing
NHTSA ODI 11641058
Oil pan developed stress crack below and along both sides of the oil pan drain plug All components are in place and there are no signs of road damage or damage do to obstacles being hit Leak started slowly and progressively became worse Returned car to have plug checked but no report back of any problem and it was documented on service order
NHTSA ODI 11640770
At gas, the vehicle jumps/judders as if it’s not getting enough gas to get up and go, and then at higher speeds it goes fine. Was reported to Horne Kia while under warranty. They never found the issues. Months later issue was found by a new mechanic, now the vehicle is no longer under warranty and the TRA codes are posted online. [XXX] Reported August 2021 [XXX] Reported December 2020 INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA ODI 11640448
I got a CEL (code P1326), three different times. Each time has been after a hard rain or a car wash. I have had to pay to have the knock sensor replaced each time, twice by a mechanic and once by a Kia dealership. There’s a recall for this issue on model years older than my 2020. I was told that Kia is aware but that there aren’t enough people having the issue to warrant them to investigate.
NHTSA ODI 11639763
The engine is burning through oil. I have already had the car checked for an oil leak. It is the engine. It's a 2020 however it does not have high mileage for the year that it is.
NHTSA ODI 11635121
I was driving on the high way and the car loose power completely have to do change oil every two weeks and can’t find a solution
NHTSA ODI 11632860
The contact owns a 2020 Kia Optima. The contact stated that the vehicle was consuming an excessive amount of engine oil. The contact stated that oil changes needed to be performed more frequently than normal. The contact stated that the oil light remained illuminated. The local dealer was not contacted. The vehicle was not repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 116,000.
NHTSA ODI 11629853
Driving at highway speed of 65 mph, the vehicle abruptly lost power. The check engine light started flashing. I was almost rear ended due to the loss of power, I was able to coast to the emergency shoulder and stop. The car was towed to the nearest Kia dealership. Diagnostics show code P1326, the engine has failed and needs to be replaced at a cost of over $10000. This the same engine that was included in a class action lawsuit for model years up to 2019, the 2020 was not included. Kia is offering no assistance to me as the second owner of the vehicle even thought the car only has 98,000 miles, the powertrain warranty is reduced to 60,000 for a second owner. The cost of repairs is more than the value of the vehicle.
NHTSA ODI 11629142
The contact owns a 2020 Kia Optima. The contact received notification of New Vehicle Limited Warranty Extension (Illumination of Air Bag Warning Light); however, the part to do the repair was not yet available. The contact stated that while starting the vehicle, the air bag warning light illuminated. The seat belt alarm chimed while the front driver seat belt was buckled. The dealer was made aware of the failure but confirmed that parts were not yet available. The vehicle was not repaired. The manufacturer was made aware of the failure and a case was opened. The failure mileage was approximately 42,860.
NHTSA ODI 11622702
Was on highway going 65, check engine light started flashing loss power. Couldn't go over 2000 rpms car would struggle to accelerate, car had been using up oil like crazy the week before. Stopped at an autozone car read code P1326.
NHTSA ODI 11619551
The contact owns a 2020 Kia Optima. The contact stated while driving approximately 45 MPH, and depressing the accelerator pedal, the check engine light was flashing. The contact stated that the accelerator pedal was being depressed; however, the vehicle failed to respond as needed. The contact pulled over, turned off the vehicle, and had the vehicle towed to an independent mechanic to be diagnosed. The mechanic retrieved DTC code: P1326; and notified the contact that the vehicle had experienced engine failure. The contact stated that prior to the engine failure, one quart of engine oil was being added weekly. The contact called a dealer however, the Service Manager did not return the call. The vehicle was not repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 117,000.
NHTSA ODI 11618726
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