The issue is with a restart after the car engaged the auto idle stop feature. Outside temperature was about 43F, Car had been driven earlier in day, and was parked for about 1 hour. The car started okay after sitting for an hour, then driven at highway speeds for about 10 mins. Car then came to a stop once coming off the highway at a red light. The car's auto idle engaged and the car's engine shut off. As the light turned green, my foot was taken off the brake to start the engine again and the car did not start. I received a message on the dash stating to place car in Park and start the engine, this was done but did not restart the engine. I shut the car off completely and had to use a lithium ion jumper battery pack to restart the engine. At that point the engine did start back immediately. Once home I tested the battery's voltage with a voltage meter, which read about 12.1V. I started the car with the voltage meter attached and voltage did not get below 10V and the car started without assistance. Thus proving that the battery is in good condition. The car was purchased in November of 2020, thus the battery about 2 years old and the car has just under 30K miles. I have not contacted the dealer yet. This is the first time this issue has occurred though there have been other times when starting from the idle stop the car has had difficulty in starting, starting this summer (July 2020). Difficulty has been noticed in the hotter or colder weather.

- Newark , PA, USA

My 2021 Honda Pilot's Idle-Stop System has been failing at random and dangerous times. The engine shuts off when Idle-Stop is engaged and as expected. However and until recently; when I release my foot from the break, nothing happens. The engine does not start. Restarting the engine has taken me to shift to park, turn the car off, wait a few minutes, and then it starts without any hesitation. Today this happened during a busy stop where I did not feel safe for myself or my passengers. The problem does not reproduce at my will or by performing any specific set of steps. After today, I'm nervous to drive with this system enabled. The problem never happens if I remember to manually disable the Idle-Stop System every time I start my car. Nevertheless, it's not a normal practice for me to have to disengage a feature that should work. This problem has not been reproduced or confirmed by a dealer or independent service center. The component has not been inspected by the manufacturer, police, insurance representatives, or any others. There were no warning lamps, sounds, messages, or other symptoms prior that would indicate an imminent failure.

- Miramar, FL, USA

My car, a 2021 Honda Pilot, has a feature called "Idle-Stop" where the engine stops when the break is depressed, when the break is released, the engine is supposed to start back up. Twice in the past week, while at an intersection, the Idle-Stop has engaged, stopping the engine, but failed to start the engine back up. After this occurs, I could NOT start the car back up, the engine would not turn over. The first occurrence was at the turn lane of a very busy intersection and there were numerous cars blocked by mine. Thankfully after about 30 minutes, the car managed to start up. I took it immediately to the Honda dealership where they said the car needed a software update. The dealership said the battery was fine and that there were no other issues. One week later, the same thing happened, I was a stop light and the Idle-Stop feature stopped the engine and it failed to start back. My 2 children were in the car this time, I felt very much that our safety was in danger. This time, I needed a jump start to get the engine started.

- Cumming, GA, USA

Auto restart stalls the car when reengaging the engine after coming to a full stop

- Annapolis , MD, USA

With the auto idle feature engaged (disengaging requires manually turning off the system with each vehicle start) while at a stop light the auto idle feature shut the engine off. Typically, when you release the brake the car start back up and you can begin to accelerate. Over the past few months the issue has stalled the engine, but restarted and give the warning "Collision Mitigation Braking System Malfunction." On the past 2 occurrences the engine has shut off completely and I have had to restart the car. This occurs when at an intersection or similar after going into a complete stop, so vehicles around you are ready to move. Once it took me opening the car door and closing it to get the electronics to allow the car to restart.

- Arlington, TX, USA

Vehicle failed to restart after stopping at a stop light while auto stop feature was on (defaults on). Vehicle was only 18 months old since purchase. Battery completely dead, only started after tow truck applied jumper for a long time. Had to be in busy six lane intersection for almost an hour. Car could not be shifted out of park into neutral to tow because push button transmission controls rely on battery power. Car is AWD. Vehicle is used mainly for 4 mile commute, often in stop and go traffic, to work and errands within that radius. I suspect the auto start feature drained the battery. The feature stops the engine anytime you come to a stop. It doesn-€™t seem to take into account how often it stops or how long the engine has been able to run and charge the battery.

- Maitland, FL, USA

I will be filing a issue with our 21 Honda Ridgeline too as the same problem has occurred in both vehicles with the same engine and transmission. This has happened a total of 3 different times. When I drive the Pilot for a long time (over 4 hours)on the expressway and then pull off on a ramp and turn left the vehicle will go into safe mode. The engine light will start flashing and you can not drive over 30 mph. The engine runs rough and idles hard. I have contacted Honda and the dealership I purchased it from. Honda has acknowledged this is a problem and has occurred multiples with many different vehicles. The dealership I work with has acknowledged the same thing as they have several vehicles that have been brought in with this problem. I have waited several months for Honda to come up with a solution, so far they have not. This is a safety concern because what would happen if this same situation came up when I'm pulling my trailer or on the expressway at higher speeds. This could cause an accident. This first started on my Pilot in December of 2021. It has happened several times since then. Every time there is no code the computer keeps, even though each time the engine light is flashing. What I have been told is the computer thinks the engine has backfired and goes into safe mode, but Honda doesn't know why it does this. If you turn the vehicle off and restart it, the problem goes away. When the dealership has run a diagnosis off the computer, there are no codes the computer throws. Even though the check engine light is flashing when this occurs.

- Richmond, IL, USA

Engine shuts off when you are at a red light and you press the foot brake pedal hard. When you release the brake the engine starts. In my case the engine shut off and when I released the brake the engine did not start had to put transmission in park and then did a restart.

- Williamsburg, VA, USA

The car's automatic engine shut-off feature when stopped at a red light failed to reengaged after removing foot from break the car shut down and the transmission button shifted into neutral and displayed a message that you must put your foot on the brake and shift the car to Park. The battery indicator light was flashing and everything turned off in the car. After doing this the car told me I must put my foot on the break and restart the car. It then allowed me to shift back into drive. The dealer was not able to recreate the issue, and no other things showed the issue other than the battery indicator lamp flashing on and off until the car was back in drive. The light I lost all power at was on a road with a 55 MPH speed limit. When the light turned green and the car lost all power there was another vehicle approaching, but I was not able to get the car moving fast enough to get out of the way.

- Powell, OH, USA

Twice in the past 4 weeks, while driving, the car switches into Neutral. The car dash still says it is in Drive and the gear buttons still show -€œD/S-€ highlighted. However, the car is rev-ing the engine as if it is in neutral and the car is only rolling instead of driving. It lasts for about 10 seconds and then resumes working normally.

- Manalapan, NJ, USA

Incident occurred 9/28/21 4:20 - 4:30 pm PST while driving in the 3rd lane of southbound 880 Highway about 1 mile before the the exit of 16th Ave & Embarcadero in the city of Oakland. The speed that the vehicle was moving at the time of the incident was between 50 to 55 MPH. The vehicle has more than half a tank of gas and the battery has never been discharged. Also all the required vehicle inspections and services has been performed by the same service center of San Leandro Honda since acquiring the vehicle on 2/10/21 from San Leandro Honda. There are 3 occupants in the vehicle; my wife, our 5 year old child and myself (driver). Our 2021 Honda Pilot EX-L with only 9,209 miles without any accident records started to show different kinds of warning signs lighting up on the dashboard, then followed by steering and engine failure. I immediately turn on the hazard lights and pointed the vehicle towards the right shoulder of the freeway. Thank goodness that at the time of the incident the traffic is heavier and moving slower. Also other motorists are accommodating enough to let us get to the shoulder without any accidents. If it was lighter traffic at the time it could have been devasted for us. Tow truck driver Manuel Escalante that works through FSP in partnership with CHP helped us get out of the shoulder of the 880 freeway onto a safer location in the city street to await further towing assistant from my roadside service with Honda. After getting towed by another tow truck driver to San Leandro Honda on 9/28/21, my vehicle still remain there. The service department haven't provided any detail report to why the engine seized from working while we were driving in the freeway.

- San Leandro, CA, USA

We just got the car from the dealer and it is still less than 200 miles and it-€™s leaking oil. There-€™s oil leaks in my garage which I thought was water coming from AC. When I check the oil dip stick. It was empty.

- Pittsburg, CA, USA