2017 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.

While driving my 2017 Acura MDX on I-35W in Fort Worth, Texas, at approximately 60 mph, the vehicle suddenly displayed a "Transmission Problem – See Manual" warning and completely lost the ability to move forward. The accelerator became unresponsive, and the vehicle would not move in Drive. We could only coast using the vehicle's remaining momentum. There were six people in the vehicle, including two children and two elderly passengers. We were in heavy highway traffic near a complex interchange, in the second lane from the left, with a very narrow left shoulder. The vehicle was rapidly losing speed while other cars continued approaching at highway speeds. We had to carefully cross approximately four to five lanes of traffic to reach the right shoulder. Other drivers honked and maneuvered around us, creating an extremely dangerous situation. If the vehicle had stopped in an active traffic lane, we could easily have been struck from behind by another vehicle traveling at highway speed. With six occupants, including young children and elderly passengers, the consequences could have been catastrophic or fatal. This sudden loss of power put not only our family but also other motorists at serious risk. We activated the hazard lights and called 911. A police officer eventually positioned a patrol vehicle behind us with emergency lights to protect the scene. The MDX was subsequently transported by flatbed tow truck. The mechanical cause has not yet been determined. The vehicle should be available for inspection upon request. I am reporting this incident because a sudden loss of the ability to move forward at highway speed is an extremely serious safety hazard that could result in a major collision, serious injuries, or loss of life.

NHTSA ID

11775092

Incident

Nov 1, 2026

As I was driving in a stop and go traffic jam, the vehicle would not go forward although I was pressing on the gas pedal, the engine stall and when it finally reacted after pressing it for the second time it went too fast that I couldn’t stop in time to avoid rear ending the other vehicle, the emergency braking system did not function properly either. This has happened multiple times even when I driven on highways and there’s incoming traffic and the engine goes on stall. But this time it led to an unavoidable accident. I have been concerned for a long time about this issue but I have never received a recall to remedy this problem.

NHTSA ID

11771499

Incident

Oct 15, 2026

Brake system, Cruise control, lane keeping system get malfunction erratically (ever since 2022, and has been like this), and one of the two sets of brakes never wears off (More than 100 K mileage now (Oct. 2026) , one set of brake pads still is still have sufficient life and does not seem to require replacement. Additiionally, recently (August 2026) the electronic system has gone very bad, the dashboard automatically restarts, headlight turns on, and trying to engaging something, then turned off automatically, then a new cycle starts, and even I turned off again, the cycle will restart until battery is drained and dead, if I do not lock the car (and I had to replace a new battery that was used for less than 1.5 year. If I lock the car, the car will start the same cycle and will honk, and honk, until the surrounding people had to remove the car.

NHTSA ID

11770295

Incident

May 3, 2022

The contact owns a 2017 Acura MDX. The contact stated that while driving, the Adaptive Cruise Control (ACC), brake, and Lane Keeping Assist System (LKAS) warning lights were intermittently illuminated. The contact associated the failure with the brake pads, which had not been replaced since the vehicle was purchased brand new; however, the dealer confirmed that the brake pads were in good condition. Additionally, the contact stated that there were electrical failures after the vehicle was parked. The steering wheel was raised, and the warning light was illuminated while making a continuous clicking sound, and the horn was honking continuously while the vehicle was parked and locked. The electrical failures caused the battery drain and the battery was replaced. The contact stated that several attempts were needed to jumpstart the vehicle. The contact stated that there was an abnormal sound coming from under the hood. The vehicle was taken to the dealer on several occasions; however, the cause of the failures could not be determined. The manufacturer was notified of the failure by phone. The failure mileage was approximately 60,000.

NHTSA ID

11769719

Incident

Oct 7, 2022

Mileage

60,000 mi

The on board camera mounted on windshield above rear view mirror has failed and now none of the safety feature function (lane keep assist, adaptive cruise, etc).

NHTSA ID

11768937

Incident

Jul 1, 2026

A lot of lights came on dash, multiple failures of systems listed. Had vehicle scanned, found code U3000-49, forward facing camera issues. Code is hard fault, will not clear. When inspecting camera, found it to be extremely hot(couldn't hold it without getting blistered)

NHTSA ID

11768075

Incident

Sep 14, 2026

The paint on my roof at the sunroof is peeling in the same exact manner the the already existing Warranty Extension: White Diamond Pearl Paint in Service Bulletin 19-029 or Models 2014-2016, I am aware that this Acura MDX is a 2017 02/17 to be exact and from the same MFG of Alabama that these issues are reported. if you look at the example pictures on the service warranty that are EXACT to the issues with the paint on mine. I have the same paint Color listed as NH603-P and I would like this covered as the year previous model.

NHTSA ID

11764045

Incident

Jun 10, 2026

When making a slow turn or rolling stop, the vehicle hesitates on light throttle and then experiences a sudden, jerky surge when the pedal is pressed further. This is very unsafe and scary for people around at school crossing and highway crossings

NHTSA ID

11763920

Incident

Sep 13, 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 - An uneven sealing surface allows moisture to enter the inner taillight(s), causing one or both of the inner taillights not to work.