2021 Honda Pilot: start-stop system problems

Filed Oct 29, 2026 · MA

My wife operates a 2020 Honda Pilot Touring, purchased new and currently with approximately 60,000 miles. The vehicle's automatic idle stop/start system intermittently shuts the engine off while stopped in traffic but fails to restart when the driver releases the brake and attempts to proceed. The driver must shift the vehicle into Park and manually restart the engine, leaving the vehicle unexpectedly immobilized in active traffic. The vehicle was previously brought to Atamian Honda in [XXX], in spring 2026 for this same defect. Honda performed a corrective repair, but the identical failure has returned approximately six months later. The driver now feels compelled to manually disable the automatic idle stop feature every time she starts the vehicle to avoid another failure. We believe this represents a serious, unresolved safety defect and are particularly concerned that the condition has recurred after a previous manufacturer-directed repair. We request that the federal safety agency document this repeated post-repair failure and consider it in its ongoing evaluation of Honda idle-stop restart safety issues. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Aug 8, 2026 · Engine · NE

Ive had about 5 times my car Honda pilot 2021 stall at a stop light, a stop sign. The first it took a minute to go and the light was green. I was honked at and yelled at. It finally kicked on and we went, the next time it went into accessory mode at a stop sign, then into N then off…. All while in drive to start. The rest were times I was in auto start stop and it just wouldn’t start. Each 5 times it gave an error code that disappeared right after I had to try snd restart by pushing the button. I went to Honda 2 times now, first time they said they did the program… that didn’t stop the issue, I then took it again after the 4th time and they said it was a bad battery… replaced it mind you $400 later… and it did it the next day.. they won’t cover a free inspection and when I said there’s a bulletin about this they said they did id already but still doing it. I am very frustrated and j drive 3 kids under 7 this is very very unsafe especially someone who already has a brain injury from aka c I dent.

Filed Jul 27, 2026 · Electrical · TX

Since 2023, this car’s auto start/stop feature has malfunctioned. Honda keeps replacing the battery and saying nothing else is wrong. It has had 4 battery replacements since 2023. Now they are saying I need to replace the starter. I no longer use the start/stop feature, but if I forget and it engages, my car will not restart leaving me in an intersection trying to get the car to restart, which in a large city is scary. They did adjust the controls one time under an extended warranty, but it did not help. The service manager says nothing else can be done, but I’m reading this is an open investigation on this issue and Honda should be replacing the starter as well. My car has had all scheduled maintenance done at the dealership and only has around 56,000.

Filed Jun 7, 2026 · Engine · IN

We had the engine serviced for recall on stop start issue on 12/4/25. On May 15, 2026 the engine failed. The dashboard came on with every warning light and a mechanic said the engine was knocking and had to be replaced. Honda denied any issue and said the timing belt had to be broken. The mechanic confirmed no issue with timing belt and said you can’t start the engine if the timing belt was broken. The mechanic said the engine was knocking and had to be replaced because the car could no longer be driven safely.

Filed Mar 19, 2026 · TX

Auto start-stop feauture turned on at complete stop at traffic light. When light turned green and pressed the gas pedal to accelerate, engine did not turn back on. It had put vehicle into neutral and would not allow vehicle to shift into any other gear. Had to shut off engine and turn on vehicle an additional 3 times to get the engine to start again and into drive. This has happened twice before within the last year with the auto start stop feauture when it turns on at a complete stop. I usually press button to turrn off auto start stop feature to prevent this known issue from happening but forgot to turn feature off. Honda wants to charge $300 to diagnosis problem with auto start stop feature due to problem being known but no recall issued.

Filed Dec 31, 2025 · Electrical, Fuel system · WA

We were driving our 2019 Honda Pilot and at a traffic light the car failed to restart after the auto stop-start system shut off the engine. This happened when I started to step on the gas so we could have been rear-ended by the car behind us. The brakes also appeared stuck when I tried to depress them so I could restart the car. There was no warning until the car refused to start, but the computer system did appear to do some sort of a reboot sequence.

Filed Dec 18, 2025 · Engine, Transmission · RI

I have had two major problems with this car. At approximately 84,000 miles, the engine started making a very loud noise, regardless of speed. It was first diagnosed by an independent service center as a control arm bearing failure. I contacted Honda Corporate and was told that it had to be diagnosed by a Honda dealer/service center. It was then diagnosed as a failure of the control arm bearing by a Honda dealer/service center. I was told the engine had to be replaced. Honda Corporate offered a 50-50 split, leaving me with a bill of $8480. This is completely unfair and unjust for me to have to pay this for a manufacturer's defect. In the second incident shortly thereafter, I was on the highway in traffic when the automatic stop-start function failed, and the car stopped and did not re-start. I had cars backed up behind me, and it was a very unsafe situation. After turning the car off completely, I managed to restart it, and got off the highway. The problem continued afterwards, and I had to turn off the function manually in order to drive the car at all.

Filed Aug 29, 2025 · OH

Car does not restart after auto start stop is engaged, car stalls at intersections, causing dangerous conditions.

Filed Aug 21, 2025 · Engine · FL

1. About a year ago the engine stop/start function started to fail intermittently. I went to the honda dealer who they charged us about $500 for a battery and never mentioned a recall or repair. 2. About six weeks ago the auto engine stop/start function failed to restart the engine after stopping. I thought it was the battery again and went back to the honda dealer. They charged about $1,500 for various things but stated that the auto stop/start function software had been updated and if there any future problems to return. 8/19/2025. We were on the interstate hwy in stop and go traffic. We were stopped in the left lane and the traffic started going again. The cars in front of us started going and we were left behind. The cars behind us went around and we were left stalled in the middle of an interstate hwy. After a few minutes I got the car running. Being stalled on the inserstate hwy is a life threating issue! I took the 2021 honda pilot to the honda dealer on 8/20/2025 who states that they cannot duplicate the problem. Please note this the third (3rd) trip to honda for the same issue. No resolution there have been many other times where this occured and I just turned the function off which only works till the next time you drive the car. Please help with this issue before someone gets hurt...

Filed Jun 23, 2025 · Electrical · 62,000 miles · OH

The contact owns a 2021 Honda Pilot. The contact stated that the idle STOP/START system suddenly activated while idling at a stop sign, stop light, and driving at slower speeds of approximately 5 MPH. The vehicle stalled while the failure occurred, causing the contact to make several attempts to restart the vehicle. The failure was more persistent. There were no warning lights illuminated. The dealer was contacted, and it was confirmed that the diagnostic test and repair were not covered under the recall. The vehicle was not diagnosed or repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 62,000.

Filed May 19, 2025 · Electrical, Engine · WA

Auto start/stop feature turned off the engine at a stoplight. When the light turned green and the brake pedal was released, the engine did not restart. There also appeared to be some sort of electrical malfunction since the start stop button would not turn off the ignition system in an attempt to reset the vehicle. This happened on a light regulated highway with a posted speed limit of 55 mph.

Filed Apr 18, 2025 · Engine · MS

This is another incident of the auto start/stop system failing to restart the engine after a stop in traffic.