2025 Honda Odyssey power train problems

“The vehicle's Auto Idle Stop (AIS) system engaged normally when coming to a complete stop at an intersection, shutting off the engine to save fuel. However, when attempting go through the intersection after the light changed to green, the engine failed to restart automatically. The vehicle completely lost power in an active lane of traffic, creating a safety hazard. The vehicle had to be shifted into park and manually restarted to clear the roadway. This failure appears directly related to NHTSA Engineering Analysis EA25004 regarding Honda/Acura Auto Idle Stop restart failures.”

“The vehicle is experiencing an intermittent but highly dangerous defect involving the factory-installed Auto Idle Stop system. When the vehicle comes to a complete stop at intersections, traffic lights, or in stop-and-go traffic, the Auto Idle Stop system engages as designed and shuts off the engine. However, upon releasing the brake pedal to accelerate, the engine fails to restart automatically. Instead of seamlessly restarting, the vehicle completely stalls in live traffic. The dashboard instruments remain on, but the engine drops completely out of operational mode. To recover propulsion, the driver must shift the vehicle entirely into Park, press the start/stop button to cycle the ignition completely off, and then manually restart the engine. This creates an immediate and severe safety hazard. The sudden, unprompted loss of propulsion leaves the vehicle completely stranded in active intersections and roadway lanes, exposing the occupants to an imminent risk of a rear-end collision. The restart delay forces the driver to perform multiple steps to reset the vehicle while traffic builds around them. The manufacturer is aware of similar systemic restart failures…”

“We have been experiencing issues with the car stalling while driving. Most recently, the car lost power a few feet into making an unprotected left turn leaving us stranded in the middle of an intersection in a vulnerable position for several minutes. This was deeply unsettling to have happen while making left turn maneuver. It seems to be a failure of the Auto Start/Stop function. After a few persistent trips to the dealer, they have now informed us that this is a known issue, but the parts are on backorder until January 2027. The workaround is turning off the Auto Start/Stop function, but this button does not have an indicator light, is not always confirmed on-screen, and is re-enabled by default EVERY time the car is started. It also appears that others have complained about this issue, and this deserves to be upgraded to a recall. It is unacceptable that a manufacturer would know about an issue with serious safety implications and not notice owners. This could have easily caused a crash and it is happening to others. This specific van is used to transport a disabled family member and outside aides often drive him in this car. We do not feel comfortable with…”

“Auto Idle start stop system failed to start vehicle while. We were stopped at a red light auto idle shut down the engine once the light turn green and we attempted to move forward the auto start failed to cycle resulting in a stalled vehicle on the road, potentially increasing risk to passengers and other drivers on the road. This has happened multiple times.”

“The vehicle idle start/stop feature has started struggling to reengage, particularly, it seems, in warmer weather. At least six times in the past two months (Sept-Oct 2026), the start fails completely during a drive. What this means is that the vehicle is stopped at a light and the start/stop kicks in. When I lift my foot off the brake to prepare to drive again, a warning flashes on (it disappears quickly but says something was detected) and the car shifts into park. I cannot put the vehicle into drive without turning off the car and turning it back on. This is very dangerous as I have been at the front of and in long lanes of traffic. Other drivers honk and try to go around me while I am getting the vehicle back up and running. The dealer has checked the car twice but cannot replicate the issue (both days they had the car, the temperature outside was below 80 degrees, and that seems to be a factor). Therefore, they cannot make or recommend any fixes other than turning off the feature everytime I turn on the vehicle.”

“There appears to be an issue with the automatic start-stop system. Occasionally, the engine will shut off at a stop light but fail to restart as expected. To get the vehicle running again, I have to turn the car off completely, wait a few seconds, and then start it back up.”