2020 Kia Optima Problems

What owners report

Complaints from 2020 Kia Optima owners in this sample center on the engine: high oil consumption, low oil pressure warnings, and knock-sensor code P1326 with limp mode and, in several cases, engine replacement. Transmission and fuel-system complaints also appear, describing stumbling or jerky low-speed behavior and occasional stalling. Reports span a wide mileage range, from just a few thousand miles to well past 150,000.

1. 1
   Engine

   Excessive oil consumption and low oil warnings

   • 74 complaints (49%)
   • median 98,000 mi at 4.2 yrs old (8 state mileage, few)
   • 3 mention a crash, fire or injury
   • owner-quoted repair $4,000 (median of 6 quotes)
   • filed 2021–2026

   Owners describe adding oil far more often than normal, sometimes weekly or every few weeks, with no visible leak. Many mention the low oil pressure light staying off or coming on only briefly at a stop, so the low level went unnoticed until a dipstick check or a shop visit. Dealers typically started an oil consumption test and, in some cases, told owners the engine needed replacement. Reported across the sample from about 39,000 to 167,000 miles, with several clustered between 50,000 and 130,000 miles.

   14 related service bulletins

   What to check: Check the oil level on the dipstick and look for a fuel smell; ask whether any oil consumption test was performed and whether the ECM software campaign was completed.

   2 excerpts from owner complaints in NHTSA records

   “I have kept up on regular oil changes and maintenance on my Kia which I bought new 5 years ago. My issues started when my car's orange check engine light came on, I experienced loss of power such as difficulty accelerating even at low speeds, especially up hill. As soon as I was able I checked my oil which and there was nothing on the dipstick. I put in 3 quarts of oil. I brought it into my usual dealership for service and let them know about the oil issue and issues with power when driving. …”

   NHTSA complaint #11699816, filed 2025-11

   “On July 4th 2023, I was driving with my son in car, when unexpectedly the check engine light came on and car lost power. We were on a highway with a 65mph speed limit. I was able to pull over to side of road. Car did Start back up, however was missing and misfiring. Shaking especially under acceleration. My engine has been consuming oil for many thousands of miles, it is documented; however only an oil consumption test was performed. Hyuandai and Kia has serious engine issues and they know it. This could've been worse. …”

   NHTSA complaint #11531589, filed 2023-07
2. 2
   Engine

   Engine knock, P1326 code and limp mode

   • 48 complaints (32%)
   • median 98,500 mi at 4.5 yrs old (4 state mileage, few)
   • 1 mention a crash, fire or injury
   • owner-quoted repair $4,800 (median of 5 quotes)
   • filed 2021–2026

   Complaints describe a flashing check engine light, sudden loss of power, shaking or knocking, and speed limited to roughly 30-50 mph, often while accelerating or on the highway. Shops and dealers retrieved code P1326 (knock sensor detection) and, in several cases, found metal debris in the oil and advised the engine needed replacement. Some owners reported the repair was not covered. Mostly reported between about 34,000 and 130,000 miles.

   6 related service bulletins

   What to check: Ask for any stored or pending P1326 history and a check of the oil for metal debris; confirm whether the knock sensor has been replaced.

   2 excerpts from owner complaints in NHTSA records

   “I was driving on the freeway and my check engine light started to flicker and I felt my car shake and going to limp mode. I made an appointment with the Kia dealership and they told me the engine is failing. They submitted a request for a Goodwill case to Kia corporation and it was denied since there’s no open recalls and is not covered by the extended warranty. …”

   NHTSA complaint #11740375, filed 2026-05

   “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 complaint #11639763, filed 2025-01
3. 3
   Transmission and drivetrain

   Dual-clutch transmission shudder and hesitation

   • 9 complaints (6%)
   • typically at 5.1 yrs old
   • filed 2021–2026

   Owners of the 7-speed dual-clutch describe jerking and shuddering at low speeds and from a stop, hesitation when pressing the accelerator, and occasional unexpected loss of speed when merging. Dealers performed a transmission software update, which owners said helped only partly, or reported they could not duplicate the condition. Some complaints involve a full transmission replacement. Described from under 5,000 miles onward, becoming more frequent in later years; complaint mileages in the sample vary widely.

   1 related service bulletin

   What to check: Test drive at low speed and from a rolling stop, and ask whether any transmission software updates or fluid services have been done.

   2 excerpts from owner complaints in NHTSA records

   “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. …”

   NHTSA complaint #11647773, filed 2025-03

   “When I accelerate the car jerks as if is going to cut off. I have taken it to the dealer, and they can not find any thing wrong. After searching the internet, I find I am not the only one with this issue. I just want my car fixed so that I feel safe driving it.”

   NHTSA complaint #11441181, filed 2021-11
4. 4
   Fuel system

   Stalling and low-speed fuel delivery

   • 15 complaints (10%)
   • median 145,000 mi at 6.9 yrs old (1 states mileage, few)
   • 1 mention a crash, fire or injury
   • filed 2021–2026

   Complaints describe stalling or surging while driving, a fuel odor in the cabin, and a dealer diagnosis of a low-pressure fuel pump needing replacement, sometimes with high-pressure pump and injector work. Several owners report the symptoms returned after repairs, and some mention being told a fix was not yet available. Reported at mileages from roughly 30,000 upward, including one at about 145,000 miles.

   What to check: Ask whether the low-pressure fuel pump has been replaced and note any fuel smell around the tank or in the engine bay at inspection.

   2 excerpts from owner complaints in NHTSA records

   “Today as I was driving to work my car suddenly stopped while being idle at the stop light. It turned off. I was able to restart and drive to work safely and home. I googled the issue and saw many Kia optima owners having the same issues and they’re saying no codes or anything popping up. Should this be considered a recall.”

   NHTSA complaint #11758538, filed 2026-08

   “I purchased in July 2020, from sept 2020 I've had it at the dealership with shuddering, stalling and loss of acceleration. I originally thought fuel pump or transmission but kia said no. then in 2022 I received a letter from kia corporate stating low pressure fuel pump failure. so i called the dealership and told them the letter states everything I had been in to see them about numerous times. made an appointment they said they found an error but had no fix. …”

   NHTSA complaint #11708981, filed 2026-01
5. 5
   Air bags

   Airbag warning light and non-deployment reports

   • 7 complaints (5%)
   • median 21,148 mi at 1.1 yrs old (5 state mileage, few)
   • 4 mention a crash, fire or injury
   • filed 2020–2026

   Some owners report the airbag warning light coming on, with the seat belt chime sounding even when belted, and say the dealer had no parts available to complete the repair. Other complaints describe airbags not deploying in a collision. Reported from around 20,000 to 43,000 miles.

   What to check: Confirm the airbag warning light does not stay on after the bulb check at start-up, and ask whether any airbag-related warranty extension has been applied.

   2 excerpts from owner complaints in NHTSA records

   “My vehicle was moving when a ford 150 pulled out in front of me. Forward collision worked & slowed the vehicle to 35mph. I hit the truck doing severe front end damage to my car. The airbags did not deploy what so ever.”

   NHTSA complaint #11378067, filed 2020-12, 4,297 miles

   “Stable track control failed to work, the driver seatbelt did not tighten & stayed loose, & air bags did not deploy upon hitting the ditch & small trees resulting after hitting ice/water upon coming to a stop sign at a “T” cross road.”

   NHTSA complaint #11715952, filed 2026-02

Buying note. Engine oil consumption and knock-related codes are the most common themes in these complaints, so a pre-purchase inspection that checks oil level, oil condition and any stored codes is worth the cost. Ask for service records covering oil changes, the ECM software campaign, and any transmission or fuel-pump work.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.