Acura MDX engine failure problems

Filed Oct 27, 2026 · Engine · 90,000 miles · FL

The contact owns a 2019 Acura MDX. The contact stated that while operating the vehicle, the engine failed to restart after the Auto START/STOP was engaged. The contact stated that while at a stop light, the engine failed to automatically restart after releasing the brake pedal. The contact shifted to park(P) and restarted the vehicle. The contact stated that the failure had occurred on several occasions. Additionally, while the contact’s wife was driving, the vehicle stalled and had to be manually restarted. The local dealer and the manufacturer were notified of the failure. The contact stated that the vehicle had experienced the failure listed in the federal safety agency Action Number: EA25004 (ENGINE AND ENGINE COOLING). The failure mileage was 90,000.

Filed Oct 15, 2026 · Engine · 70,357 miles · CA

The contact owns a 2020 Acura MDX. The contact stated that the vehicle was previously repaired under Technical Service Bulletins: 22-009, 22-024, and 23-002; however, the failure persisted following the repairs. The contact stated that while stopped at an intersection, the engine failed to restart after the Auto Start/Stop feature engaged, and the transmission independently shifted to Neutral (N). The contact shifted the transmission to Park (P) and pressed the Engine Start/Stop button to restart the vehicle. The vehicle was taken to the dealer, where it was determined that the starter required replacement. The dealer requested that the manufacturer replace the starter; however, the request was denied. The contact associated the failure with the federal safety agency Action Number: EA25004 (Engine and Engine Cooling). The failure mileage was 70,357.

Filed Oct 12, 2026 · Engine, Fuel system · MD

Driving home from a trip June 2019 on the highway at 60mph with 3 children and my husband, my 2016 Acura MDX experienced complete engine failure - alarms started to sound and I experienced a loss of acceleration, lights in the dash included Engine Problem, Transmission Problem, Emission System Problem, Critical Failure Detected Stop Driving When Safe etc. The vehicle shifted into neutral. I was able to pull off the road onto the shoulder. The engine was still running but would not shift into park. I contacted Acura TLC to have the vehicle towed but we were stranded on the side of a very busy highway in 90 degree heat with 3 kids waiting. Not only was it unsafe to be driving 60mph and lose engine power, I had to also negotiate three lanes of traffic to safely reach the shoulder. The dealership that serviced my vehicle stated it needed a "software update" - the vehicle was with them the week before this happened for regular maintenance and they failed to do the supposed software update. I complained about engine issue in this vehicle from the first time I took for service and nothing was ever done about my complaints. I have all my service records from Acura service indicating my complaints. In 2026 we took the vehicle back to Acura for diagnostics and were told the engine and transmission needed to be replaced due to a KNOWN issue by Honda Motor Corp with the transmission cooler system contamination. The repair estimate is $36,506.15.

Filed Oct 7, 2026 · Engine · NC

Dec. 16, 2025, took Acura into the dealership because Check Engine light kept coming on. They did a full inspection and said I needed to have the purge valve replaced and that it was nearing time to have other services: transmission service, front transfer case, rear differential, brake fluid, timing belt, spark plugs, fuel service. Took the diagnostic to my brother who is a mechanic and he started the work starting with the purge valve. He had already done spark plugs with oil change in Oct. 2026. Fast forward to Apr. 2026 my car starts making a weird knocking sound upon accelerating. My brother was in hospital at this time so I didn't want to stress him so I just stopped driving it. I had the other stuff done at shop he recommended but the knocking sound didn't stop. Brother told me to get it diagnosed again. Now Sept. 2026, they said I need a whole new engine, and that Acura would not cover it! What!? They felt so badly they didn't even charge me for the diagnostic. I took it to two other shops just to see if there was anything else that could be done but they all told me the same thing. It's a 2019 how on earth could it need a new engine. I've gotten ALL the work done that is recommended. I didn't even drive it when it started making that noise. My husband and I have been sharing 1 vehicle! I have not missed an oil change and had all recalls repaired there but the dealership told me since I didn't do the services in the dealership at a premium that Acura would not extend me a Goodwill to replace their faulty engine. Why would I do the work at the dealer when my brother is a mechanic and owns his own shop? I believe my engine is suffering the same issues that are causing millions of Acura owners the same dangerous recall. The last place I took the car was the Acura/Honda Specialists shop in the city where I live and this guy told me everything that was serviced looked good but the car needs a new engine and there's even metal in the oil but my VIN doesn't count!

Filed Oct 4, 2026 · Electrical, Engine · NY

On October 1, 2026 at approximately 5:45am, while driving my 2026 Acura MDX, I stopped at a red traffic light on a busy street. The vehicle's Auto Idle Stop system shut the engine off as designed. When the light turned green and I attempted to proceed, the engine failed to restart. The vehicle became disabled in an active traffic lane in the dark and I was unable to move it for several minutes. I attempted to restart the vehicle multiple times. It took several attempts to fully the shut the vehicle down and restart it before I was able to actually restart the car and resume driving. Because the vehicle was unexpectedly immobilized in traffic when surrounding vehicles began moving, I was placed at significant risk of being struck from behind or involved in a serious collision -- particularly because it was dark and all my lights were off while attempting to restart the car. My best assessment is that the failure involved the Auto Idle Stop / Restart system, starter system, electrical system or related control components. The exact cause is unknown at this time. The vehicle and all related components remain available for inspection upon request -- at least until the dealership starts working on my car to diagnose and hopefully fix the problem. (There are other reports of this happening with earlier models.) There were no warning lights, warning messages or obvious symptoms immediately before the failure. The Auto Idle Stop system appeared to operate normally when the engine shut off at the red light; the failure occurred when the system was supposed to restart the engine. The problem has not yet been reproduced or confirmed by my Acura dealer. I advised my dealership that the car failed to restart and left me stranded in active traffic. I was initially told that it could be several weeks to months before they could inspect the vehicle and I escalated the matter to the head of the service department due to the serious safety issue.

Filed Sep 21, 2026 · Suspension · NH

My 2016 Acura MDX (VIN [XXX]) is covered by Acura safety campaign 4170A8. The campaign covers rear subframe corrosion at the suspension mounting points that can cause the rear wheels to become misaligned or inadequately retained, affecting handling, stability, and braking. On XXX, I brought the vehicle to Sunnyside Acura, [XXX] (Repair Order XXX). The dealer did not perform the recall remedy and noted "cannot complete as rear toe arms are seized." They ordered replacement rear toe arms (52370-TZ5-A91 and 52375-TZ5-A91) that day. More than a month later, the recall repair has still not been completed: I filed a complaint with the dealership. They called me but did not follow through. On XXX, the dealer postponed the repair because no loaner vehicle was available. The repair was rescheduled for XXX. The dealer did not contact me. I contacted Acura Client Relations more than a week ago and have received no response. I am driving a vehicle with a known, open safety defect that Acura has acknowledged but has not repaired. I am asking the federal safety agency to help ensure Acura and its dealer complete the recall remedy promptly. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Sep 16, 2026 · Electrical, Engine · TX

I own a 2025 Acura MDX A-Spec purchased in XXX from John Eagle Acura in [XXX]. The vehicle has less than 10,000 miles. Component/system: The Auto Idle Stop/start system has malfunctioned. During the past week, the engine unexpectedly shut off while stopped at red lights and stop signs approximately 4–5 times. When it was supposed to restart, the vehicle sometimes failed to restart normally and required multiple attempts. The vehicle and components are available for inspection upon request. Safety risk: These incidents occurred at intersections while I was stopped in traffic. When the engine failed to restart, I was unable to immediately proceed while vehicles were behind me, creating a potential collision and traffic hazard. I regularly have my two young children in the vehicle, making this especially concerning. Dealer inspection: I brought the vehicle to John Eagle Acura after experiencing the problem. The service advisor indicated that this is a known issue, and the vehicle was serviced for the concern. The failure occurred repeatedly in real-world driving, but I do not know whether the dealer was able to reproduce it during inspection. Manufacturer/other inspection: The vehicle was inspected by an authorized Acura dealership. It has not been inspected by police or insurance representatives. Warnings/symptoms: I received no prior notification or warning from Acura regarding this issue. The first incidents occurred during the week before my dealership visit. The engine shut off while stopped and then did not restart normally. I did not observe a warning lamp or message specifically indicating that the vehicle would fail to restart. After experiencing the problem, I learned that the federal safety agency has an ongoing investigation, EA25-004, involving Auto Idle Stop failures on Honda and Acura vehicles, including 2023–2025 Acura MDX models. I am submitting this complaint so these repeated incidents can be documented as part of the federal safety agency's review. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 5

Filed Sep 7, 2026 · Engine · FL

"My 2016 Acura MDX completely seized on the highway after a loud knocking sound, which perfectly matches the connecting rod bearing failure under Recall 23V‑751. Even if my specific VIN isn't showing up as open on the website, I know the federal safety agency has a major open investigation into 1.4 million of these V6 engines because hundreds of vehicles are failing exactly like mine outside the original recall scope. I need Acura to open a corporate goodwill case to inspect my engine and cover this repair."

Filed Sep 5, 2026 · Engine · KS

"Vehicle experienced a sudden flashing check engine light pulled over checked oil restarted car flashing check engine light went away then started flashing again a few miles down the road (Cylinder 3 misfire) accompanied by severe engine knocking. The engine locked up/seized while hot. car was stuck on the road and was unable to shift to neutral. After cooling down, the engine restarted but produces a heavy metallic scraping and loud squealing noise from internal friction. This matches the exact failure mechanism of connecting rod bearing failure under investigation PE25008, but Honda/Acura has excluded this VIN from active recalls. I was forced to pay $389 out-of-pocket for an emergency tow."

Filed Sep 5, 2026 · Engine · MN

Engine seized multiple times. Completely broken now. Online it says many people have these problems.