2020 Acura MDX Engine Problems

See attached document for complaint.

NHTSA ID

11747720

Incident

May 14, 2026

The contact owns a 2020 Acura MDX. The contact stated that while driving approximately 20 - 25 MPH, there was an abnormal knocking sound coming from the passenger’s side of the vehicle. The contact stated that the check engine warning light and other unknown warning lights were illuminated. The vehicle stalled and was towed to dealer to be diagnosed. The dealer determined that the engine had seized. The contact associated the failure with NHTSA Campaign Number: 23V751000 (Engine and Engine Cooling); however, the VIN was not included. The manufacturer was made aware of the failure. The failure mileage was approximately 104,000.

NHTSA ID

11746661

Incident

May 9, 2026

Mileage

104,000 mi

While driving my 2020 Acura MDX, the vehicle developed an intermittent check engine light and a noticeable engine knocking noise coming from the engine compartment. The vehicle was taken to an Acura dealership for diagnosis. According to the certified Acura technician, no diagnostic trouble codes were found stored in the vehicle’s system. However, the technician confirmed there was an audible knocking noise present from the engine during inspection. The technician stated "No engine oil leaks found at this time. Engine. I did verify the noise that you are talking about far as knocking noise goes. Right now, it sounds like it's a lower end noise, possibly crank shaft related. Engine teardown would need to be in place to verify which cylinders are bad and to confirm if the bearing is gone or not.". The vehicle has all service records, including routine oil changes at recommended intervals. The technician also confirmed that the vehicle had oil in it. The vehicle is not part of the existing recall, but the symptoms and description match the known crank shaft rod bearing issue.

NHTSA ID

11737478

Incident

May 10, 2026

Interstate driving 70mph. Sudden engine power loss, vehicle slowed to 50mph. Check engine light came on. Engine knocking noises. Drove car 2 miles to our Acura dealership. Service dept says we have rod bearing failure. Currently deciding how to proceed...used or Reman motor repalcement.

NHTSA ID

11734327

Incident

Apr 24, 2026

On March 3, 2026 my son was driving our 2020 Acura MDX when we lost power in the middle of an intersection. The following day we had it towed to Montanto Acura in [XXX] where we were told we had a blown engine due to a bad crank shaft and possibly engine bearings. Prior to this the car drove fine with no warning signs. My son who was [XXX] old was at a dangerous intersection and had to wait for help to arrive to move the vehicle out of the intersection. We had to pay to replace the engine a total of $8,747.36 for a used engine. Now fearing for our son's safety we decided to sell the car at a loss and buy him something we can reply on and that won't put him in danger. Although Acura has recalled many engines, our VIN did not come up in that recall, however we have now been affected by the same issue many others had the recall performed on. I have all service records from our dealership to prove the condition. It is unacceptable that a Honda Engine would fail with 105,374 miles and all service work done at the dealership. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11729475

Incident

Mar 3, 2026

The motor through a misfire code and began making a noise while vehicle was sitting at a red light. Vehicle lost all power and had to be towed. Was quoted my the Acura dealership $9k. Main reason for addressing this concern is because numerous Acura J35 series motors have already been recalled for engine connecting rod issues. While this motor doesn't apparently fall under that recall, odd that it would essentially had the same issue, when it only had 136k miles and has been maintained to factory standards (or better)

NHTSA ID

11728187

Incident

Mar 2, 2026

MY car has 39200. Miles acura mdx 2020 tech package. Has a rod knocking sound. There was a recall number 23v751000 that i was never notified about. I cant drive car under this vondition may harm engine further. Question is this recall still valid even if I was mot informed or does my cars acura/Honda warranty covers repairs or replacement

NHTSA ID

11727655

Incident

Mar 27, 2026

While driving my 2020 Acura MDX A-Spec at approximately 63,744 miles, the vehicle suddenly lost all engine power without warning while passing through a busy multi-lane intersection. The loss of propulsion prevented acceleration and forced us to coast across traffic lanes to reach the shoulder, creating a significant safety hazard. The engine would not restart. The vehicle was inspected on 3/17/2026 by Lyle Pearson Acura (Boise, ID). The dealership diagnosed catastrophic internal engine failure with the following findings: spun rod bearing in cylinder #6, excessive metal debris in the oil pan, and bearing seizure to the crankshaft. The technician stated the failure pattern is consistent with the rod-bearing defect described in Acura Safety Recall / Service Bulletin 24-001. Although my VIN is NOT currently included in the recall population, the confirmed failure mode matches the known defect. This suggests the issue may extend beyond currently identified vehicles that are included in Acura Service Bulletin 24-001 and NHTSA recall 23V-751. The vehicle has a salvage title from prior cosmetic damage only; no engine, drivetrain, or structural components were affected. The vehicle has been properly maintained with documented service history. This failure represents a serious safety risk due to sudden loss of power in active traffic conditions, increasing the risk of collision or injury. I request NHTSA review this incident to determine whether additional vehicles should be included in the recall and to assess the broader safety risk.

NHTSA ID

11725507

Incident

Mar 13, 2026

The contact owns a 2020 Acura MDX. The contact stated that while driving 55 MPH, the accelerator pedal was depressed; however, the vehicle failed to accelerate as intended. The vehicle shook abnormally with the check engine warning light illuminated. Additionally, there was an abnormal sound coming from the engine compartment. The vehicle was driven to the residence. The contact stated that while parking the vehicle, the engine seized. The vehicle was towed to the dealer, where it was diagnosed with rod bearing failure and a failure in cylinder #6. The contact was informed there were metal shavings inside the oil pan, and that the engine needed to be replaced. The vehicle was not repaired. The contact referenced an unknown recall; however, the VIN was not associated with the recall. The manufacturer was made aware of the failure but provided no assistance. The failure mileage was approximately 86,743.

NHTSA ID

11724665

Incident

Feb 22, 2026

Mileage

86,743 mi

During the summer of 2025, the auto idle engine railed to restart while at a stop light. We had to shut off and restart the car. We took it to the car dealer and they did some sort of software update. It happened again in January 2026 while at a stop light off a highway exit ramp. We took it to a different dealer because we were living in a different city at the time. In their computer system, they could see the repair that had been done. They did some sort of other update and submitted it as a warranty repair for Acura (which the other dealer had not done). They noted there was one other repair that could be done, but Acura would not allow them to do both at once and this update usually fixed it. However, it happened again in February 2026. The engine did not restart from auto idle, this time at a stop light toward the beginning of an eight hour road trip back home. Fortunately, turning off the engine and starting it back up worked. We took it back to the second dealer and they did the additional repair authorized by Acura and submitted as a warranty repair. Three incidents of the auto-idle not restarting the engine in less than a year is not acceptable. The car is unrealiable.

NHTSA ID

11722797

Incident

Feb 23, 2026

On December 4th I noticed a rattling sound when I was driving. It worsened when my car would rev above 2RPMs and before shifting. It also would make a terrible grinding sound when I started the car. I had about 1/4 of a tank of gas and thought that maybe that was part of the issue. After filling up, the sound was not as loud, but was still present when I started the car and upon accelerating. I took my car to my Acura dealership on December 5th. Within an hour of having the car they called to tell me that the engine needed to be replaced due to a connecting rod failure. They told me that the car is no longer safe to drive and that the repairs would be required in order to continue to use the vehicle safely. There was no warning sign. My only other concern is that the downshifters of this vehicle have never worked properly. I have mentioned this to the dealership multiple times and even drove the vehicle with their representative to recreate the issue. The car would accelerate and lurch forward upon utilizing the downshift feature. This would also cause the vehicle to over-rev which I am concerned was problematic to the connecting rod failure. Additionally, the vehicle has always made a grinding noise upon starting the engine, but the dealership assured me this was normal. Acura is unwilling to cover the full cost of replacement even though this vehicle has been maintained per the manufacturer's recommendations. There are approximately 90,000 miles on this vehicle.

NHTSA ID

11711475

Incident

Dec 4, 2025

Car started to accelerate randomly and 2 seperate occasions while driving, Car started to decelerate / Brake randomly while driving

NHTSA ID

11711358

Incident

Jan 13, 2026

I was at a red light with the idle stop automatically triggered. When the light turned green, and I pressed the accelerate pedal, the car would not move. I looked and saw the car had shifted itself to N (neutral) when it should have stayed at D (drive). I pressed the "D" button to drive but it stayed in N. There was a green light around the N button indicating the selected button. I had to turn off the car, turn on the car two times before the car recognized I wanted to press the "D" button. The screen by the steering wheel had some sort of message but I don't recall what it said. The word "accessory" might have been part of the message. This is absolutely a safety risk for myself and others. I had cars behind me at the green light honking. I had to turn on the hazard lights and wave to them out the window. If the driver before me did not pay attention, they could have hit me. This is the second time this has happened.

NHTSA ID

11711138

Incident

Jan 15, 2026

There was a couple times where the car stalled at a red light. Also, there are a lot of times when I press the push to start, it will not start, advising me to place the key fob near the push to start. I find this to be dangerous when driving and very annoying when attempting to start and it doesn't start.

NHTSA ID

11709878

Incident

Dec 31, 1969

My 2020 model Acura MDX is experiencing unexpected engine shutdowns while braking during motion. The issue has been reported multiple times to the vehicle manufacturer and their authorized dealers; however, their responses have been consistently unhelpful and have not resolved the problem. I currently have an open complaint with American Honda Motor Co., Inc. since December 2023 Case Number: 14329512 Additionally, I have found numerous reports online from other owners of the same model experiencing the same issue, as documented here: 🔗 2020 Acura MDX Engine Complaints – CarComplaints.com This recurring malfunction presents a serious safety risk, especially in moderate traffic conditions, where sudden engine failure during braking could lead to collisions or injuries.

NHTSA ID

11700564

Incident

Nov 7, 2025

I was driving on the interstate when suddenly the check engine light began to flash and the car lost power. I was traveling at 70 mph and the sudden loss of power caused the vehicles behind me to move into the other lane to prevent rear ending me. While there was no accident, there could have been if the other drivers were not reactive. There was no advanced warning. This could have been deadly for me and my family. I was several miles from home and needed to have the vehicle towed to a mechanic who stated it sounded like a rod bearing and suggested we take it to an Acura dealer. We are yet to have a resolution.

NHTSA ID

11700169

Incident

Nov 15, 2025

At a red light or stop sign, my MDX switches into Neutral without me knowing it. When I press the gas to go, my car won't move. Other vehicles behind me almost hit me as they expect me to go. I can't switch into drive. I must turn off car and then turn it back on. I feel this is very dangerous. This happens about once a week now. The MDX was just in for service and recalls a few months ago. Nothing was noted about the engine on the reports.

NHTSA ID

11689382

Incident

Sep 24, 2025

The contact owns a 2020 Acura MDX. The contact stated that occasionally, while driving at various speeds, the vehicle stalled. There was no warning light illuminated. Additionally, while the vehicle was stopped at a traffic light, the Auto Idle START/STOP failed to operate as designed, and the vehicle failed to restart. The vehicle was taken to a local dealer; however, the cause of the failure was unknown. Upon further investigation, the contact related the failure to an unknown recall; however, the VIN was not included. The manufacturer was made aware of the failure. The failure mileage was approximately 10,000.

NHTSA ID

11688166

Incident

Jan 15, 2021

Mileage

10,000 mi

When the vehicle stops and the idle auto-start/ stop engages, the vehicle will automatically go into neutral and cannot be restarted until the vehicle is turned off then back on. This has happened at both stop lights and on the highway and almost caused a very serious rear end accident.

NHTSA ID

11688065

Incident

Aug 26, 2025

The idle stop feature does not work correctly. A couple times the car did not restart while stopped at a red light. Had to put into park and took about a minute to restart.

NHTSA ID

11686206

Incident

Aug 12, 2025

The contact's relative owns a 2020 Acura MDX. The contact stated while driving approximately 25-30 MPH, the check engine warning light started flashing, and the vehicle stalled and lost electrical function. The contact stated that the vehicle was only able to be locked manually, and the windows failed to roll up as intended. The driver was able to pull over to the side of the road. The vehicle failed to restart and was in the process of being towed. The dealer was notified of the failure and informed the contact that the earliest availability for a diagnostic test was in 7 days. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 65,000.

NHTSA ID

11684465

Incident

Aug 31, 2025

Mileage

65,000 mi

I own a 2020 Acura MDX. The Auto Engine Idle Stop system failed to operate while depressing the accelerator pedal while at a stoplight. The vehicle shifted automatically to neutral and would not let me switch to drive. I just recently purchased this car (less than two weeks). Based on what i see online and all the complaints on here , this is a known issue. However when i contacted my local Acura they acted as if they never heard of this issue and they want to diagnose my car at my expense. The mileage on my vehicle is between 31,000 and 32,000. I purchased this vehicle to accommodate my newborn granddaughter. Now, I don't feel like its the safe vehicle its advertised to be. This is a very dangerous thing that is happening, how many complaints need to be submitted before the manufacturer is held accountable.

NHTSA ID

11684446

Incident

Aug 31, 2025

1. The car accelerates by intself. The accelaration is like "hiccups". When reversing and changing to D gear, it takes longer than usual for the accelarion to take effect. Yes, car is available for inspections 2. It is dangerus because it gets the hiccups even at high speeds. If it is a serious egine problem, which seems like it is, could cause an accident. 3. The car was taken to the dealership for 3 recalls but it got worse after the recalls were fixed. Supposedly the recalls were supposed to fix the issues. We have not taken it back yet. 4. There is no lights or warnings when it does it.

NHTSA ID

11683334

Incident

Aug 27, 2025

The contact owns a 2020 Acura MDX. The contact stated that on several occasions, while coming to a stoplight, the vehicle lost motive power. There was no warning light illuminated. The vehicle was able to restart. The vehicle was taken to the dealer; however, the vehicle was not diagnosed or repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 46,000.

NHTSA ID

11683177

Incident

Aug 26, 2025

Mileage

46,000 mi

connecting rod bearing failure confirmed by independent mechanic. No alerts or warning lights. Problem just showed up and engine started knocking on acceleration.

NHTSA ID

11681023

Incident

Aug 13, 2025