There are 50 owner-reported engine complaints for the 2020 Kia Optimain NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
The contact owns a 2020 Kia Optima. The contact stated that while driving at an undisclosed speed, and while the vehicle was parked, there was a loud banging sound coming from the engine compartment. There was no warning light illuminated. The RPM failed to operate as intended while driving. The vehicle was taken to an independent mechanic, where it was diagnosed, and determined that there were metal shavings inside the engine, causing engine failure. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The mechanic referred the contact to a dealer for additional assistance. The vehicle was taken to the dealer; however, the vehicle was not diagnosed or repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 69,751.
The rod barring failed in my engine. I broke down in the middle of the parkway with my daughter. This is my third Kia optima that has had this issue but the dealership is stating there is not a recall on this model. The check engine light did not come on except when the car lost all power.
The contact owns a 2020 Kia Optima. The contact stated that while the vehicle was at a full stop, the red oil warning light illuminated; however, after driving off, the warning light disappeared. The vehicle was driven to an independent mechanic where it was diagnosed with an oil pump failure caused by low oil pressure while the vehicle was stationary, and the RPM was low. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 167,000.
My car burns oil. I had to have my spark.plugs and engine coils replaced. I was driving and my check engine light came on. Also, my car was sputtering like you wouldnt believe. When i had the spark plugs and ignition coils replaced, the spark plugs were covered in oil. Last year, I got an oil change and within a few weeks the oil was empty. A neighbor told me my car was burning oil. I also took it to an independent mechanic and he said that was an issue with the kia optima.
The contact owns a 2020 Kia Optima. The contact stated that the vehicle was sputtering and vibrating abnormally while starting. There were no warning lights illuminated. The failure was intermittent but became a recurring failure. The vehicle was towed to an independent mechanic out of fear of the vehicle stalling on the highway. Prior to the engine failure, the contact became aware that there were oil spots where the vehicle was parked. The vehicle was diagnosed, and the mechanic sealed two holes in the oil pan and replaced the spark plugs that were fouled by engine oil. The vehicle was repaired; however, the failure reoccurred. The contact stated that the check engine warning light was illuminated. The vehicle was taken back to the same mechanic who diagnosed the vehicle and determined that the spark plugs were covered in oil again. The contact was advised to take the vehicle to a dealer to check for engine failure. The vehicle was taken to the dealer, and an oil consumption test was performed; however, the vehicle failed the oil consumption test. The dealer had not yet diagnosed the vehicle, but suggested that the engine needed to be disassembled to check for engine wear. The vehicle was not repaired. The manufacturer was informed of the failure. The failure mileage was 91,185.
While driving, the vehicle experienced a sudden loss of engine power and entered limp mode. The check engine light began flashing and the vehicle had very limited acceleration, creating a safety concern when driving in traffic. The vehicle was towed to a Kia dealership for diagnosis. The dealer retrieved diagnostic trouble code P1326 (Knock Sensor Detection System – range/performance). During inspection, the dealer found metal contamination in the engine oil and oil control valves and advised that the engine has internal damage and requires replacement.
Took to Kia for engine burning excessive oil. They determined the cylinder wall was scorched due to piston ring. The warranty people say it’s normal wear and tear and won’t honor the warranty. It’s still sitting in their engine bay because they want me to pay for the diagnostic which I don’t have. $4000 roughly for that but it needs a new engine. The warranty should be covering this! NEVER PAY FOR AN EXTENDED WARRANTY!!! They will not help you
Vechile is burning oil and knock sensor came on which indicated rod bearing. While driving the car lost power the check engine came on was abl to pull over and turned off the car. Did not drive it was tow home.
I got the car was running good week or 2 later I see the oil light flash after my oil change I go back top it off repeat the cycle almost weekly burning losts of oil then I get a code p1326 for a knock sensor same day car go into limp mode no power rpm won’t go over 2 car won’t go over 60-65 I park it go outside to take it to the dealership next day it ain’t start I haven’t had the car 4 months only have 138,000 miles
Out of the blue I get a code for a misfire on cylinder one. Got in to head to work as normal and it was stalling and shaking so bad that I am scared to drive it. The next day the check engine light was on when I started it to seek out the issue. Car was manufactured in September 2019 but is the 2020 model year. I was told by a license mechanic this is related to an internal Kia engine issue. I contacted 800 333 4KIA to see if this was a known issue that they had a solution to. Of course I was told to self repair that my VIN is not covered under the recall. Can you tell me how Kia assumes that engine issues with the 2019s model year would have been fixed before the 2020 models were assembled? Sounds like my dream car is now my nightmare. 3rd White Kia Optima but I am likely leaving the Kia family if this requires a new engine.
It is an oil burner and engine failed and went into limp mode less than 5 years when drove off dealership brand new.
Metal contamination found on VVT solenoid of 2020 kia optima 2.4L GDI engine. Firestone Autocare Confirmed metal debris in oiling system. Vehicle exhibits symptoms identical to prior theta II bearing recall SC172/SC200/SC227 but not covered under recall range.
My car has been burning oil rapidly. I’ve contacted kia over this issue and I have had several times where I have had to continually add oil. There is no leak. This is a known issue with kia motors across mechanics nationwide and there should be a recall issued. This has been at several shops and over the last few years. This motor should NOT be consuming 4 quarts of oil within 1000 miles after an oil change.
Without warning my car went into “Limp Mode” while driving on the highway almost causing a collision as I was forced to pull off the road on the highway. Flashing engine light car would not accelerate and was shaking dramatically. Was forced to wait for a tow on a busy highway. P1326 code. Rod knock. A known issue for the Theta II engine. Many recalls have been made for this exact engine for these exact problems but for some reason the 2020 Kia Optima is not included even though it is the same engine covered by lifetime warranty from the 2019 models due to these recalls and know issues. There’s plenty of recorded cases all over the web and is a wide concern for many affected Kia drivers. Kia does not offer the same KRDS update to 2020 Kia drivers as they do to earlier models even with the same engine failure issues so we don’t even get the benefit of possible early detection. Car is well maintained and inspected at a local American tire depot and I am still forced to deal with unwarranted engine failure on a known defective engine solely because KIA will not offer help for affected customers. The 2020 KIA Optima equipped with the Theta II 2.4L engine is not safe and is a known defective product. Action and accountability are needed.
I’ve been told by multiple Kia dealerships that my Kia needs a new engine however I am barely outside of their class action lawsuit so they are not willing to settle with me. They recently within the last two months came out with two recalls that did not fix the issue.
Burning oil, not wanting to accelerate properly on the freeway, kia has engine in previous years having the same issue, and these 2020 and they are not trying to fix them.
I took my vehicle to the dealership in Chantilly, VA on May 17, 2025. On July 24, 2025, I discovered that my vehicle had no oil, despite being approximately 4,000 miles away from my next scheduled oil change. I have video documentation confirming that there was no oil in the vehicle. The car was towed back to the dealership; however, no corrective action was taken. The dealership offered to perform a test, which I declined, as this issue did not exist before servicing my vehicle at their location. Additionally, no explanation or guidance regarding the oil was provided to me. I was only advised to pay for another oil change, or a 205 dollars to diagnose the car. Subsequently, I took the vehicle to Fairfax Auto Shop, where a dye test was conducted to check for oil leaks. While no leaks were found, they advised that the vehicle has an oil consumption issue. They recommended that I monitor and top off the oil every 1,000 miles and return for oil changes every 2–3 months.
Car consumes a lot of oil. Approximately 5 quarts per week-faulty engine parts allowing oil to seep into the combustion chamber. The oil is then ignited along with the fuel, creating blue-tinted exhaust smoke. It is burning out spark plugs which is then wearing them out and almost caused car accident when car started sputtering and would not barely go once pressing gas. Has been inspected by KIA dealership. Was told engine needs to be replaced-warranty expired and nothing can be done. Car only 2 years old when this problem started and they will not replace.
Engine failure do to excessive oil consumption. I do have records. Not able to file now. Please contact if needed Thank you
engine's knock sensor
Showing 1–20 of 50 complaints
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 26, 2026