2020 Kia Optima: engine knocking or ticking

Filed Oct 28, 2026 · Engine · NC

On October 25, 2026, while traveling eastbound on US Highway 74 near Bryson City, North Carolina, my 2020 Kia Optima 2.4L GDI experienced a sudden and substantial loss of engine power while driving through mountainous terrain. The check-engine light began flashing, and the vehicle entered what appeared to be reduced-power or limp mode. The engine remained running, but acceleration and available engine power were significantly reduced. This created a serious safety concern due to the mountainous highway conditions and surrounding traffic. I immediately pulled over at the first safe opportunity and did not continue driving the vehicle. My partner, who was approximately six months pregnant, was traveling with me. We remained stranded along the roadside for approximately three hours awaiting assistance, approximately 202 miles from home. Diagnostic trouble code P1326 was subsequently identified. There were no noticeable knocking, rattling, or ticking noises before or after the incident. The oil-pressure warning light did not illuminate. After the incident, the engine oil level was checked and found to be between the minimum and maximum dipstick markings. Timestamped photographs were taken during the towing process and at dealership drop-off. The vehicle was transported to a Kia dealership, where a bearing clearance test was performed and passed. The dealership also identified an external oil leak. However, the cause of the sudden loss of power and P1326 activation has not been conclusively established. I am reporting this incident because the unexpected and substantial loss of engine power while driving on a mountainous highway created a potentially dangerous situation. I am concerned that the condition could recur and pose a safety risk to other drivers and passengers.

Filed Oct 8, 2026 · Driver assistance, Engine · SC

At around 103K miles, I took to the dealership for a multipoint inspection for knocking when braking and my forward collision/lane assist systems going offline mid drive. I learn I have to replace my axle, despite replacing my axle in sept 2025. I return a week after due to the red oil light blinking on randomly, and when I checked the oil myself it was dry. The braking and assumed wiring issues remained. I find out that my oil is low despite an oil change July 16th 2026. It is October 8th 2026 as I type this. I am doing an engine flush in hopes to improve oil consumption, but i have since learned that my engine may fail from these other Kia stories. I have not stalled or had engine failure yet but now I am worried about having to sell my car to avoid having to keep replacing the same flawed parts over and over, or worse injuring myself while driving it. I was hoping to take a trip but now I have to rent a car and play another 1,600 dollars for the engine flush which I have no guarantee will actually work. I am disgusted, and there should be consequences for KIA (and many other companies) for taking advantage of their customers. I need a new car now!

Filed Oct 1, 2026 · Engine · GA

purchased this vehicle on June 18, 2024, as a second owner with 125,019 miles on the odometer. Within months of purchase, the engine began exhibiting symptoms consistent with connecting rod bearing failure: engine knock, excessive oil burning (requiring oil top-ups every 2-3 weeks), and rough running. The check engine light illuminated with diagnostic code P1326 (Knock Sensor Detection System warning). I took the vehicle to Kia Stonecrest dealership for diagnosis. Kia informed me that the engine failure is not covered under warranty because I am not the original owner. A independent mechanic at Lions Auto evaluated the engine and quoted $4,800 for full engine replacement. THE DEFECT: This vehicle is equipped with a Theta II 2.4L GDI engine identical to engines in 2011-2019 Kia Optimas and Kia Sorento models that were subject to multiple recalls (including the federal safety agency Recall 17V‑224) and a $1.3 billion class action settlement. The defect is manufacturing debris left in the crankshaft oil passages during production, which restricts oil flow to connecting rod bearings, causing premature bearing wear, engine seizure, and potential engine fire. KIAS KNOWLEDGE AND RESPONSIBILITY: Kia had clear notice of this defect years before the 2020 model year was introduced. Despite this knowledge, Kia continued manufacturing 2020 and later Optimas with the identical Theta II 2.4L GDI engine without remedying the manufacturing process. The class action settlement litigation was filed in 2017 and covered model years through 2019; however, Kia’s decision to exclude 2020 models from coverage despite using the same defective engine creates an unjust gap in consumer protection. SAFETY CONCERN: Connecting rod bearing failure can cause sudden engine seizure while driving, resulting in loss of power steering and brake assist, creating an immediate crash hazard. The symptoms I experienced — engine knock and P1326 code — are documented precursors to catastrophic failure.

Filed Sep 22, 2026 · Engine, Transmission · TX

While driving to work, my 2020 Kia Optima suddenly lost engine power and went into limp mode in the middle of the highway, leaving me stranded and creating a severe safety hazard in traffic. The check engine light immediately started flashing and displaying diagnostic code P1326 which indicates an abnormal engine and/or a catastrophic rod bearing failure. This problem has been confirmed by the Kia dealership along with a 3rd party auto repair shop. However, Kia is refusing to cover the inspection, diagnostic, or any repairs due to the vehicle not having any open recalls, having more than 100k miles and the model of my vehicle despite this being a well known and documented manufacturing defect issue to these engines. The vehicle is currently available for inspection.

Filed Sep 8, 2026 · Engine, Transmission · TX

While driving, my 2020 Kia Optima suddenly lost engine power and went into limp mode on the road, leaving me stranded and creating a severe safety hazard in traffic. The vehicle threw diagnostic trouble code P1326, which indicates a catastrophic rod bearing failure. The problem has been confirmed by a Kia dealership scanner. However, both the dealership and Kia America are refusing to cover the inspection and repair under their safety campaigns or goodwill due to the vehicle having 180,000 miles, despite this being a well-documented manufacturing defect inherent to these engines. Prior to the failure, the check engine light started flashing. The vehicle is currently available for inspection.

Filed Jul 19, 2026 · Engine · PA

My engine failed while driving which put me and others at risk. It was confirmed by the Kia dealership as rod bearing failure. Which is a known recall on the Kia 2.4L Theta II engine. My specific VIN number is not listed on the Kia recall list. And Kia is stating that it does not qualify for a warranty replacement. Although it is the same engine with the known defect.

Filed May 7, 2026 · Engine · AR

Out of town July 12th 2025 my 2020 Kia Optima engine started having problems. I tried to get to my hotel but it was obvious I was not going to make it. I pulled into the nearest station and was told my car had no oil. There were no signs of leaking oil and no warning lights so they changed my oil and I was able to made it home. Shortly after I broke down again at night and pulled into a parking lot again no warning and no oil. I had to call someone to get oil and from that point on I had to put oil in my cart every other day with no signs of a leaks and no warning lights. It has become to dangerous to drive and the engine has now failed and knocking and shaking has caused me to park my car and not drive it. I am deeply concerned about the risk of catastrophic engine failure and the potential for fire, which has been documented in similar cases. Despite having the Knock Sensor Detection System installed, my vehicle continues to exhibit these dangerous symptoms. I sought assistance from Landers Crain dealership and KIA; however, they declined to properly evaluate or service my vehicle along with KIA declining according to the KIA Regional Manager. This lack of support has left me with an unsafe, undrivable car and no clear path toward resolution. The Center for Auto Safety Key Affected Vehicles (2.4L GDI) Kia Optima 2011–2018 (some 2019) exact same engine in 2020 Optima Kia Sorento 2012–2019 Kia Sportage 2011–2018 (some 2019) Details of the Recall and Settlement The Problem Manufacturing debris and tight tolerances can cause connecting rod bearings to fail, causing knocking, seizure, and potential engine fires. The Fix Dealers will update the software with a Knock Sensor Detection System (KSDS) to detect rod bearing issues before failure. My Optima has the KSDS installed but failed. Warranty Extension As part of a class action settlement, Kia extended the warranty on these engines to 15 years or 150,000 miles, provided the KSDS update is installed.

Filed Jan 8, 2026 · Engine · GA

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.

Filed Dec 16, 2025 · Engine · NM

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.

Filed Dec 13, 2025 · Engine · GA

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

Filed Sep 4, 2025 · Engine · IN

My engine is burning lg amounts of oil. There has been a lawsuit regarding the same issues with Kia engines (specifically up to 2019 Optimas). The Theta 2 engine lawsuit is regarding excessive oil consumption/burning, knock sensor issues, and deeper engine issues. This has been an ongoing issue for me and is ultimately affecting my engine. Kia will not cover the defects or repair expenses despite knowing the concerns with prior Kia Optima engines.

Filed Sep 1, 2025 · Engine · CA

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.