2025 Acura MDX Complaints

ENGINE — Filed 09/01/2026

I have had a problem with the "Auto Idle Stop" in my 2025 Acura MDX. While at a stop light 2 different times and at a stop sign 1 time the car engine shut off as it should. Upon letting off the brake and pressing the gas the car would not go. It stayed in Park and I could not get it to go. The engine would not turn back on. I received a warning light that said "depress brake and push start". Upon doing this the car still would not start. I had to open the door, shut door, push brake and then start the car. Dealer confirmed that this has been an issue.

ENGINE — Filed 10/10/2026

My 2025 Acura MDX A-Spec Advance (VIN [XXX]) twice failed to restart after the Auto Idle Stop system shut the engine off — on XXX (~2:00 PM CDT) and again on October 10, 2026 (2:20 PM CDT). The vehicle was immobilized and would not restart. Sterling Acura of Austin ([XXX]) diagnosed a failed starter on XXX: bench testing showed 9.7 amp draw with voltage drop below 7.3V. The dealer replaced the starter motor (part 31200-5MR-A03) under warranty, test drove 10+ miles, cleared codes, and verified the repair. A no-restart after auto idle stop leaves the vehicle without motive power in traffic, which is a safety hazard. This matches the subject of NHTSA Engineering Analysis EA25004 (No Restart After Auto Start/Stop Engages, 2016–2025 MDX). INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ELECTRICAL SYSTEM — Filed 10/13/2026

Faulty and auto-stop/start system glitch where the engine fails to turn back on. This issue frequently occurs while driving in traffic or at a stop light. This issue happens daily become extremely dangerous as car unexpected turns off and fails to turn back on a busy road. There is no option to turn off the auto-stop/start system to avoid the glitch.

ELECTRICAL SYSTEM,UNKNOWN OR OTHER,ENGINE — Filed 08/01/2026

On two occasions my vehicle stalled out when the idle stop feature failed to restart the engine in traffic. I could not restart my vehicle initially and it took several attempts to restart. Because I was at a stop in an intersection waiting to turn this could have resulted in a serious accident. There was no warning light or other indication of an issue prior to, during, or after the first incident. This was subsequently reproduced and documented with the dealer. They indicated they are seeing issues with many other vehicle of the same model and year but indicated they couldn't say much more. The dealer said they would replace the starter but did not definitively say it would solve the issue. Because they did not have the part in stock thet advised me to continue driving in the meantime with the idle stop feature disabled; however, operators must remember to do this manually at each drive.

ELECTRICAL SYSTEM,ENGINE — Filed 09/25/2026

The Auto Idle Stop has activated normally at traffic lights, but on two occasions the engine shut off and then failed to automatically restart when I released the brake. A yellow warning light with an exclamation mark also appeared on the dashboard. The most recent incident happened yesterday, 09/25/2026. There have also been several other times when the engine did restart, but it took noticeably more effort or longer than normal to restart from Auto Idle Stop.

POWER TRAIN,ELECTRICAL SYSTEM,ENGINE — Filed 04/17/2026

My 2025 Acura MDX completely stalled in active roadway traffic and failed to restart. The failure occurred during a routine stop in traffic, tied to the Auto Idle-Stop / restart sequence: when releasing the brake pedal to accelerate, the engine did not restart, leaving the vehicle completely dead and stranded in the travel lane, creating a severe risk of a rear-end collision. I brought the vehicle to an authorized Acura dealership for repair. The dealership diagnosed the issue and replaced the starter motor under warranty. However, shortly after picking up the vehicle, the exact same failure occurred again in traffic. The vehicle was brought back in, and the 12V battery and charging system were tested and deemed functional, but the vehicle continues to stall and fail to restart. Replacing the starter and testing the battery has not resolved this recurring defect, which leaves the vehicle intermittently immobilized in active traffic lanes.

ENGINE — Filed 09/19/2026

Car engine went into idle mode while the Idle Stop was engaged while stopped on an expressway off ramp. Car engine did not turn back on and entire car shut down. It took about 1 minute to re-start the car and engine. Safety was compromised because car shut off in an unsafe location. No accidents or injuries occurred. This happened about a year ago and car battery and starter were replaced by the Acura Dealer November 2025. There were no warning lights or messages prior to this problem appearing. Prior to this event, car had been slow to turn over for about 1 week. I previously submitted a complaint to NHTSA in Fall 2025, case #11694662, when this happened the first time.

UNKNOWN OR OTHER — Filed 09/16/2026

The engine shut off at a red light via Auto-Stop and failed to restart, leaving the vehicle stranded in active rush hour traffic until a manual restart of the engine was performed. This issue has occurred multiple times now.

ELECTRICAL SYSTEM,ENGINE — Filed 09/16/2026

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 NHTSA 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 NHTSA's review. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ELECTRICAL SYSTEM — Filed 09/14/2026

Auto Start/Stop At stop light car wouldn’t start after engaging Auto Start/Stop, had to turn on hazards, turn car off and restart with cars bearing down on me Monday 9/14, before entering traffic I stopped and Auto Start/Stop engaged but car wouldn’t start Got a jump and brought to dealership and they replaced starter motor

ELECTRICAL SYSTEM — Filed 09/10/2026

Auto start-stop system stalled my car at a red light few times. Also I can clearly tell starting/cranking it is lagging as well.

ELECTRICAL SYSTEM — Filed 09/12/2026

Battery keeps dying. Faulty starter leaving car stranded.

ELECTRICAL SYSTEM,SERVICE BRAKES — Filed 09/09/2026

20 minutes after parking my car, it would not start. Several different codes came up on the gauges - BRAKE issue; hill issue;stabilization issue - multiple icons and warnings. I ended up having to be jumped off.

ELECTRICAL SYSTEM — Filed 09/09/2026

Car at a stop light, went into idle stop, and then shut off with an error message that to continue to drive, depress brake pedal and push switch. Car then needs to be restarted. This has happened 3 times in less than a week, so it is becoming concerning as a safety issue. The issue seems to be related to the starter and idle stop feature.

ELECTRICAL SYSTEM — Filed 03/25/2026

Occassionally when the "auto stop start" feature is on and I am stopped at traffic light, the engine does not restart when I release the brake and hit the gas pedal. I took my car into my local dealer and they replaced battery but I was also advised that I might not want to use the "auto stop start" feature because it is a real drain on battery. Even with the new battery, I have experienced failure of the car to restart after being stopped in traffic while the "auto stop start" is engaged. When in traffic and you expect the car to restart and it doesn't, it causes momentary panic and is very unsafe. I have been turning the "auto stop start" feature off every time I start the car to avoid this unsafe situation.

ELECTRICAL SYSTEM,FUEL/PROPULSION SYSTEM — Filed 09/08/2026

Auto Stop/Start fails to restart intermittently causing dangerous situations stuck at lights unable to move. Sometimes it restarts again after pressing the brake and ignition right away. Sometimes it takes a minute to restart. Either way it happens unexpectantly leading to being frozen until you figure out what is going on.

ENGINE — Filed 09/03/2026

I was driving w a passenger on a busy 4 lane road and trying to make a left turn. When I tried to hit the gas after coming to a stop, my car would not move. I did not know what was happening, as it turned out the car had shifted into park and turned off. Extremely dangerous scenario. I had to take my foot off the brake, restart the the car and put it in drive again to move. I brought it to the dealer the following day, they said they fixed it with a gear shield as the trans had dirt in it and a new starter. However, yesterday, prob about 6 or so months later it happened again. I went directly to the dealer. They kept the car over night. Today I was told the my battery charge was too low and the auto idle engine on/off turned off due to it being not having enough charge. Totally different excuse than the first time. Also, when I dropped it off I was told someone else had dropped their 2025 MDX off that same day for the same reason. I am very concerned, worried and nervous when I drive it. It helps if I turn the auto on/off idle stop off, but I must do that every time I start the car as it resets each time the car is turned off. Obviously I forget sometimes. It is a major concern that I feel the dealership is not taking seriously or showing much concern for my safety. Thank you for your help.

ENGINE — Filed 08/31/2026

I have a 2025 Acura MDX SH-AWD. Several times while stopped in traffic, the Auto Idle Stop system shut the engine off and the vehicle displayed ‘RESTART ENGINE.’ The vehicle did not restart automatically. I'm concerned that this could cause a safety hazard if it happens in traffic. I want to file a safety complaint.

ELECTRICAL SYSTEM,ENGINE — Filed 03/13/2026

When at a red light the engine cuts off and does not restart when foot comes off the brake. Sometimes it takes several minutes to start. We were stuck in an intersection and almost were rear ended. Took it ti the dealership. had a new battery up in. By the time we got home, it did it again. Took it back to the dealership, they replaced the started. No problems for 4 months. Now it is doing the same thing again, along with the air conditioner not cooling. The first time we took it in for oil change we told them it was not cooling and were told there was nothing wrong with it. Took it back this weekend and found out there is a compressor issue. The compressors are not available for repair. Other minor issues are codes are randomly appearing on the gauges and the screen blacks out.

POWER TRAIN,ELECTRICAL SYSTEM — Filed 08/16/2026

The auto shutoff and restart system has failed multiple times causing the car to shutoff in the middle of traffic. This has happened in traffic on the interstate, on surface streets and in the drive thru line. Safety was put at risk as had to restart car in middle of traffic multiple times; once car would not restart at stop light. This could have caused an accident as vehicle was at a full stop with cars coming up from behind in the road. Dealer has replaced starter and relay twice. In less than 2 years, I'm on my third starter. Dealer has inspected vehicle multiple times. No warning messages or other symptoms before occurring. When the engine would not restart at intersection, warning message of "transmission system problem, apply parking brake when parked. See your dealer" Could not restart engine.

UNKNOWN OR OTHER — Filed 06/01/2026

My 2025 Acura MDX has 21,000+ miles on it and the START STOP SYSTEM has stalled and failed to restart the engine at RED LIGHTS several times. This is a SERIOUS SAFETY CONCERN! Does Honda/Acura have a Technical Service Bulletin for this issue? Reading many other complaints on social media many people are looking for ways to electrically circumvent the Start Stop System but that voids the manufactuers warranty. I need help solving this problem through HONDA/ACURA the right way. Please help?

UNKNOWN OR OTHER,ENGINE — Filed 08/26/2026

Idle Auto Start/Stop will not restart after cutting on leaving me stranded in traffic.

STEERING,SERVICE BRAKES,FORWARD COLLISION AVOIDANCE — Filed 08/07/2026

Hello! I am writing to report an urgent and serious safety failure involving my 2025 Acura MDX A-Spec and to request immediate investigation and action. The vehicle’s driver-assist systems - specifically the lane departure warning and forward collision warning - failed to operate. In addition, both the steering wheel and the accelerator became stuck, causing my vehicle to collide head‑on with oncoming traffic. These failures placed my life and the lives of others in immediate danger. I previously opened a case with Acura Contact and Client Relations (Case #16550271). To investigate my vehicle failures that caused this major accident, the response I received was inadequate and deeply concerning. During my conversation with Acura representatives, I was told verbally without any willingness to provide this statement in writing that Acura “has nothing to do with inspecting their own car.” Instead, I was instructed to have my vehicle inspected by my insurance company, despite the fact that they are not certified to evaluate Acura safety systems and do not possess the diagnostic equipment required to assess failures of this nature. Given the severity of the malfunction and the resulting collision, I am requesting that Acura immediately arrange a proper inspection by qualified Acura technicians and provide a written explanation of how such critical safety and control systems could fail simultaneously.

UNKNOWN OR OTHER — Filed 01/07/2026

Sunroof exploded while driving on the interstate. A loud noise and glass was everywhere inside the truck on my passenger and I. The distraction caused me to slam on brakes injuring my foot in which I’m out of work for 4 weeks

AIR BAGS,FORWARD COLLISION AVOIDANCE — Filed 05/09/2025

(1) My airbag's did not deploy when an another car drove into the front of my car causing extensive damage. It has been deemed a total loss by Liberty Mutual (claim #[XXX]) and will be towed in a day or two to their salvage yard from the auto body shop. (2) Based on what I was told by the claim adjuster, body shop and police they didn't understand why they didn't deploy, especially since one of the air bag sensors was directly in front of the impact. (3) No - Acura has not been easy to communicate with and assigned me a case #[XXX] but after I answered their questions by email a few days ago they have stopped communicating with me. (4) The car has been inspected by the body shop and Liberty Mutual. (5) No INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)