NHTSA owner reports · September 18, 2026 snapshot.
Engine complaints
164 reportsClear category filterMileage unknown · Mar 21, 2025
Electrical SystemEngine
There appears to be an issue with Kia USA regarding an oil switch fault that the company may be aware of but has not addressed through a service bulletin. We own a 2017 Kia Optima with a 2.4L engine and 84,000 miles that has recently started experiencing an intermittent oil pressure light. Thinking the issue was covered under wa…
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There appears to be an issue with Kia USA regarding an oil switch fault that the company may be aware of but has not addressed through a service bulletin. We own a 2017 Kia Optima with a 2.4L engine and 84,000 miles that has recently started experiencing an intermittent oil pressure light. Thinking the issue was covered under warranty, I took the vehicle in for repair, only to receive a quote of $6,000. The faulty switch had pushed oil through the wiring harness, contaminating the powertrain control module and fuel injectors. I have found information indicating that Kia issued a service bulletin in April 2022 for the same switch used in the 2.4L issue affecting 2015-2018 Kia models with 3.3L engines. However, when I provided this information to the dealer, they insisted the switch in my Optima was different and not covered by the bulletin. I have repeatedly requested the part number for the faulty switch referenced in the bulletin, but have not received a response from the dealer or Kia corporate. The information I found on-line is that the switch in both motors are the same switch. I understand that if this issue is not addressed early, the repair cost can reach upwards of $7,500. If Kia had proactively notified 2.4L owners about the switch issue in 2022, my problem may have been caught and resolved before the extensive damage occurred. Furthermore, if the faulty switch was used across multiple Kia models during the same time frame, the company should have included those vehicles in the service bulletin. I am not concerned with getting my own Optima repaired, but I find it unacceptable for Kia to take advantage of customers in this manner. An $18 part failure should not result in such significant damage, and Kia's lack of transparency and action is disappointing. I hope that by sharing this experience, Kia will be compelled to address this issue and prevent further financial hardship for their customers.
NHTSA ODI #11649658
Mileage unknown · Mar 17, 2025
Engine
1.) What component or system failed or malfunctioned? Engine failure due to excessive oil consumption and/or a malfunctioning Knock Sensor Detection System (KSDS). •The engine failed at only 50,000 miles due to internal issues. •The KSDS system triggered a flashing check engine light, but Kia refuses to cover the repair despite …
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1.) What component or system failed or malfunctioned? Engine failure due to excessive oil consumption and/or a malfunctioning Knock Sensor Detection System (KSDS). •The engine failed at only 50,000 miles due to internal issues. •The KSDS system triggered a flashing check engine light, but Kia refuses to cover the repair despite known past issues. •Kia engineers and the dealership confirmed the engine failure but are denying warranty coverage. ➡ The vehicle is currently at the dealership and available for inspection. 2.) How was your safety or the safety of others put at risk? •A flashing check engine light appeared, indicating possible catastrophic engine failure while driving. •Loss of engine function on the road could have led to an accident. •The KSDS system was designed to prevent this type of failure, but it failed to stop the damage in time. •If the engine had completely failed at highway speeds, it could have created a dangerous situation. 3.) Has the problem been reproduced or confirmed by a dealer or independent service center? ✅ Yes, the issue was confirmed by the Kia dealership. •The dealership confirmed that the engine has failed and needs to be replaced. •A tech line case was opened with Kia engineers, who confirmed the failure. •Kia refuses to cover the repair, claiming it is a "top-end failure" instead of a "rod bearing failure." 4️.) Has the vehicle or component been inspected by the manufacturer, police, insurance representatives, or others? ✅ Yes, it was inspected by the Kia dealership and Kia engineers. •A tech line case was created, and Kia engineers reviewed the issue. •Kia admitted that the engine failed but refused to cover the repair under warranty. 5.) Were there any warning lamps, messages, or other symptoms of the problem prior to the failure, and when did they first appear? ✅ Yes, a flashing check engine light appeared due to the Knock Sensor Detection System (KSDS). •The same warning code had previously appeared while
NHTSA ODI #11648736
Mileage unknown · Feb 25, 2025
Engine
I have been dealing with an engine issue for almost two years now, dealership is telling me I need to wait till a barring goes out for the engine to be replaced at no charge. Car does not go over 60 mph, oil is burning like crazy
NHTSA ODI #11644890
Mileage unknown · Feb 25, 2025
Engine
My Engine is burning a quart or more of oil a week. Since my last oil change I have put in 15 quarts of oil. I called KIA service department and they said there is nothing they can do unless my check engine light is on.
NHTSA ODI #11644864
80,000 miles · Feb 14, 2025
Engine
The contact owns a 2017 Kia Optima. The contact stated while the vehicle was parked, the vehicle stalled. The oil change warning light was illuminated. The contact stated that an oil change was needed almost every two weeks. The vehicle was taken to an independent mechanic where it was diagnosed and determined that the alternato…
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The contact owns a 2017 Kia Optima. The contact stated while the vehicle was parked, the vehicle stalled. The oil change warning light was illuminated. The contact stated that an oil change was needed almost every two weeks. The vehicle was taken to an independent mechanic where it was diagnosed and determined that the alternator needed to be replaced. The vehicle was repaired; however, the oil change warning light was illuminated. The vehicle was taken to a dealer where the vehicle was diagnosed; however, the result of the diagnostic test was unknown. The vehicle was repaired; however, the oil change warning light remained illuminated. The contact research and was made aware of NHTSA Campaign Number: 18V907000 (Fuel System, Gasoline, Engine); however, the VIN was not included. The manufacturer was not notified of the failure. The failure mileage was approximately 80,000.
NHTSA ODI #11642742
Mileage unknown · Jan 27, 2025
Engine
Yes, the issue has been confirmed by Kia. They acknowledged the high oil consumption and indicated that the engine requires a rod bearing replacement. However, Kia does not want to fully recognize the problem. I have taken the car to another mechanic who confirmed that the ignition coil has burnt on cylinder number 3 and identif…
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Yes, the issue has been confirmed by Kia. They acknowledged the high oil consumption and indicated that the engine requires a rod bearing replacement. However, Kia does not want to fully recognize the problem. I have taken the car to another mechanic who confirmed that the ignition coil has burnt on cylinder number 3 and identified it as an engine failure along with the high oil consumption.
NHTSA ODI #11638978
Mileage unknown · Dec 5, 2024
Engine
The contact’s daughter owns a 2017 Kia Optima. While the contact’s daughter was driving at an undisclosed speed, there was a loud rattling sound coming from the front end of the vehicle. The check engine warning light illuminated. The contact stated that while attempting to start the vehicle, the vehicle failed to start on the f…
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The contact’s daughter owns a 2017 Kia Optima. While the contact’s daughter was driving at an undisclosed speed, there was a loud rattling sound coming from the front end of the vehicle. The check engine warning light illuminated. The contact stated that while attempting to start the vehicle, the vehicle failed to start on the first attempt. The vehicle started on the second attempt was able to be driven. The vehicle was taken to the dealer who determined that the engine rod had failed, causing complete engine failure. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The contact became aware that the vehicle was included in an undisclosed Product Improvement Program for a software update; however, the contact was unaware of the software update which voided the Extended Warranty for the engine repair. The manufacturer was made aware of the failure and opened a case. The manufacturer referred the contact to the NHTSA Hotline to report the failure. The failure mileage was unknown.
NHTSA ODI #11629027
Mileage unknown · Nov 13, 2024
EngineFuel/propulsion System
A auto repair shop said my Kia Optima has a bad knock sensor which is a common problem with those cars. My safety and others was put at great risk when I suddenly lost power on the freeway Problem was confirmed at an independent service center Has not yet been inspected by manufacturer Warning message came up at the same time as…
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A auto repair shop said my Kia Optima has a bad knock sensor which is a common problem with those cars. My safety and others was put at great risk when I suddenly lost power on the freeway Problem was confirmed at an independent service center Has not yet been inspected by manufacturer Warning message came up at the same time as losing power
NHTSA ODI #11625072
Mileage unknown · Oct 11, 2024
Engine
Took the car to the dealership to diagnose an issue that I know Kia has a settlement for which is the engine class settlement and the dealership is trying to say the cause of known issue is from another source so they do not have to cover the cost of a replacement engine. The dealership is saying my option is to pay 8-10k for a …
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Took the car to the dealership to diagnose an issue that I know Kia has a settlement for which is the engine class settlement and the dealership is trying to say the cause of known issue is from another source so they do not have to cover the cost of a replacement engine. The dealership is saying my option is to pay 8-10k for a new engine when it should be covered under the lifetime engine warranty which they confirmed I have. Engine light popped up the day of taking it to dealer. The engine has the possibility of seizing putting the driver or others at risk of serious accident.
NHTSA ODI #11619423
Mileage unknown · Sep 18, 2024
EngineSeat Belts
Engine is burning 2 QT of oil every month and burning it in under 1000 miles. Kia dealership says it's a common issue but can't help me until the engine seizes up. The car has less than 85k miles on it. How can this be a common issue but they can't fix it till the engine dies? What if the engine dies out of warranty? Then I'm ou…
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Engine is burning 2 QT of oil every month and burning it in under 1000 miles. Kia dealership says it's a common issue but can't help me until the engine seizes up. The car has less than 85k miles on it. How can this be a common issue but they can't fix it till the engine dies? What if the engine dies out of warranty? Then I'm out 12k for a new engine that will die in 80k miles. This should be a recall.
NHTSA ODI #11615129
Official recalls
3Aug 24, 2023
Kia America, Inc. (Kia) is recalling certain 2016-2017 Rio, 2016-2018 Optima, 2017-2018 Optima Hybrid and Optima Plug-in Hybrid vehicles. The trunk latch base may crack, preventing the opening of the trunk from the inside. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 401, "Internal Trunk Release."
Consequence & remedy
Consequence: A person inside the trunk compartment may become trapped, increasing their risk of injury.
Remedy: Dealers will replace the trunk latch base subassembly, free of charge. Owner notification letters were mailed October 19, 2023. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC278.
Dec 19, 2018
Kia Motors America (Kia) is recalling certain 2011-2017 Optima, 2012-2017 Sorento and 2011-2018 Sportage vehicles that previously received an engine replacement under recall number 17V-224, warranty, or the Knock Sensor Detection System (KSDS) Product Improvement Campaign. The high pressure fuel pipe that connects to the fuel pump outlet may have been damaged, misaligned or improperly torqued during the engine replacement procedure, possibly causing a fuel leak.
Consequence & remedy
Consequence: A fuel leak in the presence of an ignition source can increase the risk of a fire.
Remedy: Kia has notified owners, and dealers will inspect and replace the fuel pipe, as necessary, free of charge. The recall began January 17, 2019. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC172.
Additional source detail variants (2)
Engine
Kia Motors America (Kia) is recalling certain 2011-2017 Optima, 2012-2017 Sorento and 2011-2018 Sportage vehicles that previously received an engine replacement under recall number 17V-224, warranty, or the Knock Sensor Detection System (KSDS) Product Improvement Campaign. The high pressure fuel pipe that connects to the fuel pump outlet may have been damaged, misaligned or improperly torqued during the engine replacement procedure, possibly causing a fuel leak.
Consequence: A fuel leak in the presence of an ignition source can increase the risk of a fire.
Remedy: Kia has notified owners, and dealers will inspect and replace the fuel pipe, as necessary, free of charge. The recall began January 17, 2019. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC172.
Fuel System, Gasoline:delivery:hoses, Lines/piping, And Fittings
Kia Motors America (Kia) is recalling certain 2011-2017 Optima, 2012-2017 Sorento and 2011-2018 Sportage vehicles that previously received an engine replacement under recall number 17V-224, warranty, or the Knock Sensor Detection System (KSDS) Product Improvement Campaign. The high pressure fuel pipe that connects to the fuel pump outlet may have been damaged, misaligned or improperly torqued during the engine replacement procedure, possibly causing a fuel leak.
Consequence: A fuel leak in the presence of an ignition source can increase the risk of a fire.
Remedy: Kia has notified owners, and dealers will inspect and replace the fuel pipe, as necessary, free of charge. The recall began January 17, 2019. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC172.
Mar 8, 2018
Kia Motors America (Kia) is recalling certain 2017-2018 Kia Optima hybrid vehicles. These vehicles are equipped with a Voltage Protection Device (VPD), designed to protect the high voltage battery module, that may activate inadvertently.
Consequence & remedy
Consequence: If the VPD activates while the vehicle is being operated in Electric Vehicle (EV) mode, there may be a loss of power, increasing the risk of a crash.
Remedy: Kia will notify owners, and dealers will remove the VPD switch and install two newly designed Battery Management Systems (BMS) that contain Overvoltage Protection Devices (OPDs), free of charge. The recall is expected to begin May 2018. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC162.
Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗
NHTSA investigations
3DP22003 · Loss Of Motive Power
Opened Sep 12, 2022 · Closed Dec 12, 2023
Status: closed (inferred from source dates) · Engine
The National Highway Traffic Safety Administration (NHTSA) received a letter dated July 13, 2022, petitioning the Agency to initiate a safety defect investigation into loss of motive power allegations attributed to oil drain pan assembly failures on certain Hyundai Motor America, Inc. and Kia America, Inc. vehicles spanning Model Years (MY) 2005-2021. The Petitioners cited examples of complaints indicating that the subject vehicles were experiencing rapid loss of engine oil due to oil drain plug back outs, resulting in loss of motive power and/or catastrophic engine damage. Additional complaints were provided which alleged that the oil drain pans lack sufficient structural integrity and are susceptible to cracking. The petition itself can be reviewed at NHTSA.gov under ODI number 11481745. On September 12, 2022, the Office of Defects Investigation (ODI) opened Defect Petition (DP22-003) to evaluate the Petitioners’ request. The Petitioners have provided additional complaints within four supplemental letters dated January 31, 2023, March 21, 2023, May 23, 2023, and August 4, 2023. ODI’s evaluation included the review and analysis of the complaints and supporting information submitted by the Petitioners, as well as additional complaints submitted directly to NHTSA which referenced either the oil drain plug or a crack in the oil pan. After reviewing the available data, ODI has not identified evidence that would support opening a defect investigation into the oil drain pan assemblies of the subject vehicles. Based on a review of the available information, a loss of motive power resulting from an oil drain plug back out has not occurred between the initial sale of a vehicle and the completion of its first oil change. If during an oil change service, a technician fails to remove the existing drain plug gasket before installing a new gasket, it is likely that a proper seal between the drain plug and the oil pan will not be made. An improper seal between the drain plug and oil pan could lead to the backing out on the drain plug, resulting in the sudden loss of oil while driving. Additionally, the provided examples of oil pan cracks were localized to the immediate vicinity of the oil drain plug and/or appeared to be the result of direct-contact with a tool during servicing. There is no information to support that a vehicle-based defect exists relating to the oil pan assembly, and instead the documented incidents are related to the failure to follow the proper maintenance procedures during oil change service. In October 2023, Hyundai published a Technical Service Bulletin (TSB) that provided detailed instructions for oil change service on its gasoline powered vehicles, specifically highlighting the need to remove and replace the existing drain plug gasket prior to reinstalling the drain plug. After a thorough review of the material submitted by the petitioner, the information already in NHTSA's possession, and the potential risks to motor vehicle safety implicated by the petitioners' allegations, NHTSA does not believe that a formal investigation is warranted. Therefore, the petition is denied. A Federal Register Notice (FRN) further detailing NHTSA’s reasons for denial of the petition will be published. The reference numbers for the complaints to NHTSA cited by the petitioner can be found in the petition submission documents in the public file for DP22-003. To review those complaints and the additional complaints ODI added to its evaluation which are cited in the Closing Resume ODI Report Identification Number document, go to NHTSA.gov.
EA21003 · Engine Fires
Opened Dec 22, 2021 · Closed Feb 5, 2024
Status: closed (inferred from source dates) · Engine
On March 29, 2019, the Office of Defects Investigation (ODI) opened two Preliminary Evaluations (PE19-003 on Hyundai and PE19-004 on Kia) to broadly investigate incidents of non-crash fires (regardless of origin or operational status of the vehicle) on various model year Hyundai and Kia vehicles. During the PE investigations, Hyundai and Kia issued several recalls to address vehicle fires, including those due to engine failures involving various engine types. The remedies for the engine failure recalls typically involve engine inspection (to detect existing damage), and if necessary, engine replacement. Additionally, both manufacturers have been installing an engine control software modification known as Knock Sensor Detection Software (KSDS) which is intended to detect impending engine failure, alert the driver, and limit engine power (to lessen likelihood of engine failure).KSDS is being installed under recalls and non-safety field actions, and both companies have extended limited engine warranties (see recall files). On December 22, 2021, ODI upgraded PE19-003 and PE19-004 to this Engineering Analysis (EA21-003, covering both Hyundai and Kia) to evaluate the scope of the prior recalls related to engine failures/fires and the efficacy of the recall remedies for the recalls, as well as the long-term viability of related programs and non-safety field actions being conducted by Hyundai and Kia. The former issue involved approximately 550,000 MY 2013 Hyundai Elantra, MY 2011 Kia Sorento, and MY 2012-2015 Kia Rio. The latter issue involved approximately 2.5 million recalled vehicles, which have been identified as displaying potential remedy concerns: Hyundai recalls 15V-568, 17V-226, 20V-746, and 21V-727; and Kia recalls 17V-224, 19V-120, 20V-750, and 21V-844. Regarding the recall scope issue, among all of the scope vehicles identified at EA opening, ODI found only the MY 2011 Kia Sorento vehicles equipped with both the Theta II 2.4L 4-cylinder Multi-Point Injection (MPI) and the Lambda II 3.5L 6-cylinder MPI engines experienced relatively high rates of reported fires. In December 2023, Kia issued recall 23V-877 that will cover about 80,000 MY 2011 Kia Sorento vehicles equipped with the Theta II 2.4L MPI engines. The remedy will involve an inspection, and if necessary, a replacement of the engine, as well as the installation of KSDS. It should be noted that in 2021 these vehicles were included in a KSDS product improvement campaign with warranty extension. For the MY 2011 Sorento vehicles equipped with the Lambda II 3.5L engines, ODI believes that future engine failures/fires involving these vehicles will likely be due to a lax in adhering to the proper or scheduled engine maintenance (regular engine oil changes), rather than a design or manufacturing engine issue. Regarding the issue of the efficacy of the recall remedies, ODI found the majority of the recalled Hyundai and Kia vehicles, by model, experienced lower reported fire rates after the remedies were applied. Furthermore, ODI found that for most vehicles that did not receive the recall remedies, by model, experienced relatively high fire rates. To address this problem, Hyundai informed ODI in December 2023, that it will renotify all of its owners covered by the Hyundai recalls of engine failures/fires every 8 months for the next 3 years. In December 2023, Kia stated that it will renotify the majority of its owners every 8 months for the next 3 years.Several previously recalled Kia models are excluded from the renotification due to their lower reported rates of engine fires. Overall, the renotification actions will help to increase the recall completion rates, thus reduce the frequency of engine fires in the future. In view of the recall action being taken by Kia and renotification actions being taken by both Kia and Hyundai, ODI is closing this Engineering Analysis. Also, both companies have been released from the 2020-iniated Consent Orders (Kia since November 2022 and Hyundai since November 2023). The agency reserves the right to take additional action if warranted by future circumstances. To review the reports cited in the Closing Resume ODI Report Identification Number document, go to NHTSA.gov.
EA19001 · Electrical Overstress
Opened Apr 19, 2019 · Closed Sep 19, 2024
Status: closed (inferred from source dates) · Air Bags: Air Bag/restraint Control Module
The Office of Defects Investigation (ODI) opened this investigation to determine if the failure of airbags to deploy during severe crashes, in certain vehicles, was the result of a safety related defect. During the investigation a complex failure was studied that can result in non-deployment of subject vehicle air bags and other restraint system devices in severe crash events. The subject vehicles may be equipped with an airbag control unit (ACU) for the supplemental restraint system (SRS) Electronic Control Unit (ECU) manufactured by ZF-TRW. The ECU receives signals from crash sensors mounted in the vehicle and deploys the vehicle air bags and seat belt pretensioners in accordance with manufacturer design specifications. The ECU in the subject vehicles contains a model DS84 application-specific integrated circuit (ASIC) which controls the communication of the crash sensor signal, firing commands (i.e., when to deploy the airbag(s) and/or pretensioners), and fault information (e.g., diagnostic trouble codes). In September 2016, FCA announced recall 16V-668 for certain model year (MY) 2010 to 2014 Chrysler, Dodge and Jeep products manufactured with the subject ZF-TRW ACU. In this recall, FCA discussed an EOS condition that resulted in a failure of the subject DS84 ASIC, which caused air bag non-deployment. FCA noted that the defect condition had only been observed in vehicles equipped with sensor harnessing routed across the front of the vehicle. Other FCA vehicles that also used the subject ACU, but were not equipped with cross-car harnessing, had not experienced EOS failures, despite similar time in service. During the course of this investigation, ODI sent two separate Information Request (IR) letters to six vehicle manufactures (including FCA, Hyundai, Honda, Kia, Mitsubishi, and Toyota) and one IR letter to ZF-TRW. These IR letters resulted in ODI receiving comprehensive data from these manufacturers and suppliers. Studies of this data found that the DS84 ASIC does not have sufficient protection against negative electrical transients or electrical overstress (“EOS”) that can be generated in certain severe crashes. An electrical transient occurs when the electrical power supplied to a circuit changes momentarily over a short duration of time. In these severe crash cases, the crash sensors and other powered wiring can be damaged and short circuited so as to create a negative electrical transient of sufficient intensity and duration (that are outside the vehicle manufacturer's specification) to damage the ASIC before the restraint device deployment signal is received by the SRS ECU. This damaged signal can lead to incomplete or nondeployment of the air bags and/or pretensioners. Airbag non-deployment and/or lack of pretensioner operation can increase the risk or severity of injury in a crash.A total of 8 fatalities and 14 injuries were associated with known EOS events. The common element in all investigated manufacturers vehicles is the SRS ECU containing a DS84 ASIC manufactured by ZF-TRW. The risk associated with the ASIC is equally shared among all OEMS involved in the investigation. The actual real-world risk can be mitigated by other factors which were assessed by ODI during this investigation. The first mitigating factor involves protections built into the ACU design which protect the DS84 ASIC from damage. There are multiple strategies and levels of protection employed by different OEMs that provide effective EOS mitigation. The two most common strategies at the ACU level are circuit protection diodes on the remote senor signal lines, and current limiting resistors that protect critical components. The second mitigating factor is found at the vehicle level and involves the location and routing of the wires leading from the crash sensors to the SRS ECU. If the wires are well protected in a crash and are not routed with other power wires carrying large currents, the risk for an EOS event is significantly reduced or eliminated. These design specific factors combine to produce a spectrum of risk for the vehicles equipped with ACUs using the DS84 ASIC. Given the many of years of field exposure, it is possible to divide the subject population into two groups; vehicles which have experienced EOS events, and vehicles which have not experienced EOS field events. Four of the six OEMs involved in this investigation have experienced EOS field events on at least one of their models equipped with a DS84 ASIC. All vehicle models (including the Toyota models identified in the Failure Report Summary of the opening resume for this investigation) with field events have been recalled. In an abundance of caution, ODI kept this investigation open five years to monitor field performance and did not identify any field events on vehicles not included in existing safety recalls. Given the spectrum of risk identified in this investigation and that all vehicles with a demonstrated unreasonable risk have been recalled, ODI is closing this investigation. ODI is closing this investigation with the following manufacturer safety recalls: 16V-668, 18E-043, 18V-137, 18V-363, and 20V-024. With the recall actions taken by the subject vehicle and equipment manufacturers, this investigation is closed. The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exists on other model or model year vehicles outside of the recall scopes. The agency reserves the right to take further action if warranted by the circumstances.