2018 Acura MDX

The Office of Defects Investigation (ODI) has received 414 reports of connecting rod bearing failures in the 3.5L V6 engine used in the following vehicles: Model Years (MY) 2018-2020 Acura TLX, MY2016-2020 Acura MDX, MY2016-2020 Honda Pilot, MY2018-2020 Honda Odyssey, and MY2017-2019 Honda Ridgeline.  The subject engine failures were analyzed as part of a Recall Query (RQ24013).  It was determined that these engine failures are outside the scope of Honda Recall 23V-751. Further, evidence gathered in conjunction with RQ24013 does not suggest this failure is caused by the same crankshaft manufacturing defect that is addressed by Honda in Recall 23V-751.  Based on analysis of data from RQ24013, NHTSA has closed that investigation. The significant number of reports of engine failure in vehicles outside the scope of RQ24013 presents a potential safety risk that warrants further investigation.  ODI is opening this Preliminary Evaluation (PE) to further evaluate the scope and severity of the potential problem and to fully assess the potential safety-related issues.  To review the ODI reports cited in the Opening Resume ODI Report Identification Number document, go to NHTSA.gov.

On June 3, 2022, the Office of Defects Investigation (ODI) opened Preliminary Evaluation PE22005 after the agency received VOQs and several field reports concerning the Auto Idle Stop (AIS) feature on 2016-2019MY Honda Pilot vehicles. The complaints allege that the engine fails to restart on its own from a complete stop at a traffic light or road intersection with the AIS function engaged. The subject vehicles are equipped with a 3.5L engine with a 9-speed automatic transmission. On January 6, 2023, Honda released service bulletins 23-008 and 23-009. These service bulletins address the failure to restart issue in the 2016-2019MY Honda Pilot vehicles, as well as the 2015-2020 Acura TLX, 2016-2020 Acura MDX, 2019-2022 Honda Passport, and 2020-2023 Honda Ridgeline vehicles. The repair outlined in the service bulletins is a two-stage countermeasure to remedy the issue. The first stage is a Programmed Fuel Injection (“PGM-FI”) software update. The second stage is only deployed if the software update fails to remedy the issue. The second stage, depending on the model and model year, consists of replacement of the starter assembly, starter relays, and a valve adjustment. Additionally, Honda extended the warranty coverage to 10 years with unlimited mileage for vehicles requiring the second stage component replacement. ODI continues to receive complaints of the AIS failure to restart, with many complainants alleging the campaign countermeasures had been completed.NHTSA has reviewed Honda's Information Request Letter responses involving warranty claims, lawsuits, and consumer complaints in addition to ODI's own data. This Engineering Analysis is being opened to further consider the potential safety defect, including gathering additional data regarding Honda’s service campaign efficacy. ODI is additionally expanding the scope to encompass all vehicles addressed in Honda’s service bulletins 23-008 and 23-009 as well as newer model year vehicles, which are substantially similar to the vehicles covered by the service campaign. To review the ODI reports cited in the Opening Resume ODI Report Identification Number document, go to NHTSA.gov.

On November 8, 2024, the Office of Defects Investigation (ODI) opened Recall Query RQ24013 to assess the scope of Honda recall 23V-751 after receiving complaints that alleged connecting rod bearing failures in vehicles that were not within the scope of recall 23V-751. In November 2023, Honda recalled 248,999 various Model Year (MY)2016–2020 Honda and Acura vehicles equipped with the 3.5L V6 engine. Honda recalled these vehicles due to a crankshaft manufacturing defect that caused premature connecting rod bearing wear and engine seizure. While the out-of-scope failures involved in these complaints appear to have a very similar failure mechanism as the recalled engines, a thorough analysis of all available data from Honda has not indicated that the same manufacturing defect exists in the out-of-scope engines as the engines recalled by 23V-751. Based on this analysis ODI has determined that Honda has properly defined the scope of recall 23V-751. Consequently, ODI will close this RQ investigation.  NHTSA will continue to investigate these complaints of engine failure as part of a new Preliminary Evaluation Investigation (PE25008). The Agency reserves the right to take additional action if warranted by new circumstances.

Odometer Fraud. The contact purchased a 2018 Acura MDX on August 26, 2026. While registering the vehicle, the contact was informed that the previous title indicated that the odometer was reported at 277,000. The vehicle was a private sale. At the time of purchase, the mileage was 77,000.

NHTSA ID

11769279

Incident

Aug 26, 2026

Mileage

277,000 mi

All the light light up

NHTSA ID

11768154

Incident

Sep 30, 2026

The contact owns a 2018 Acura MDX. The contact stated that while driving at an undisclosed speed, the vehicle lost motive power but was able to restart. On another occasion, while the contact's husband was driving 10 MPH, the vehicle lost motive power in the middle of the highway. The vehicle was unable to restart, and the contact's husband had to push the vehicle to the side of the road. The vehicle was towed to a service center, where it was diagnosed with fuel pump failure. The contact was informed that the fuel pump needed to be replaced. The vehicle was repaired. The manufacturer was made aware of the failure by telephone. The failure mileage was approximately 136,000.

NHTSA ID

11767678

Incident

Sep 1, 2026

Mileage

136,000 mi

Hi I'm very disappointed because my 2018 Acura MDX got stolen on 8/11/25.. Unbelievable because got stolen from my driveway and i had a keys ..also it was super quick because my neighbors camera recorded the moment.. I need some recompensation because it's unbelievable how weak security Acura MDX and tlx has because last Saturday my son's 2020 Acura tl got stolen from his house same thing he has car keys but Acura is gone do something ASAP

NHTSA ID

11767600

Incident

Aug 11, 2025

The vehicle was being driven and the dashboard was lit up with all the systems in error related to ACC (Adaptive Cruise Control)

NHTSA ID

11764124

Incident

Sep 11, 2026

driver seat rocking. Acura stated 2018 recall for this issue was vin number specific and does not include my vehicle however this is the issue with my driver seat. they advise repairs at my expense.

NHTSA ID

11761364

Incident

Jan 1, 2024

The contact owns a 2018 Acura MDX. The contact stated that while driving at various speeds, the vehicle went into LIMP Mode and failed to exceed 35-60 MPH. The check engine warning light was flashing. The driver pulled over to the side of the road. The vehicle was restarted, reset, and operated as intended. The vehicle was taken to the dealer, where the failure could not be duplicated, and the failure persisted. The contact's brother, a certified technician, advised the contact not to turn off the vehicle after the failure occurred to prevent the system from resetting. The contact followed the instructions, and the contact's brother retrieved DTC: P0304, indicating a cylinder 4 misfire. The vehicle was not repaired and would be taken to the dealer. The manufacturer was notified of the failure, and a case was filed. The failure mileage was approximately 87,000.

NHTSA ID

11759230

Incident

Jul 24, 2026

Mileage

87,000 mi

The car has started with an auto high beam, lane assist, lane departure, crash mitigation, adaptive cruise lights coming on one after the other noting there are issues with the systems and they are disabled. Code is U3000 using a scanner noting Multipurpose Camera Unit Internal Electronic Failure. Sometimes the code will clear, and sometimes not. If it clears an entire drive cycle may be completed just fine, sometimes it pops back up before even moving the car and sometimes during the drive. This is a safety concern as these systems not working or stopping working mid drive and affect safety. The repair for this is not clear and a failure of a safety system should not be occurring on cars without an inmediate and covered fix. The average car on the road is over 12 years old so this failure is occurring on cars well newer than the average car and compromising safety of the driver and surrounding cars especially features intended to prevent crashes that drivers rely heavily on. The fact it can stop working mid drive is a huge hazard since one may be relying on a system and it suddenly fails (like adaptive cruise control) and cause a crash. Please investigate his widespread issue and please fix it.

NHTSA ID

11755732

Incident

Jul 24, 2026

Service Bulletin - Under certain circumstances, after coming to a stop and the idle stop feature engages, the vehicle may not automatically restart. In other circumstances, vehicles may experience a slow crank or fail to start under hot ambient temperature conditions.

Dealer Message - Under certain circumstances, after coming to a stop and the idle stop feature engages, the vehicle may not automatically restart. In other circumstances, vehicles may experience a slow crank or fail to start under hot ambient temperature conditions. The customer should be able to restart the vehicle by selecting Park and pushing the ENGINE START/STOP button.

Owner Notification Letter - Under certain circumstances, after coming to a stop and the idle stop feature engaging, the vehicle may not automatically restart. Acura is providing a product update with a new PGM-FI software update to fix this issue.

Service Bulletin - An uneven sealing surface allows moisture to enter the inner taillight(s), causing one or both of the inner taillights not to work.

Service Bulletin - An uneven sealing surface allows moisture to enter the inner taillight(s), causing one or both of the inner taillights not to work.

Service Bulletin - Under certain circumstances, after coming to a stop and engaging idle stop the vehicle may not restart automatically due to excessive cylinder pressure and/or low cranking torque. Typically, the client can immediately restart the vehicle by selecting Park and pressing the ENGINE START/STOP button.