2024 TOYOTA GRAND HIGHLANDER Vehicle Speed Control Problems

My vehicle has been out of service since October 7, 2025 due to a complete failure of the instrument cluster (combination meter). This issue is related to SAFETY RECALL 25TA08. The instrument panel is fully non-functional, making the vehicle unsafe and inoperable. The vehicle has been at Toyota dealership for approximately three months, with no repair completed and no clear timeline provided. The dealership stated they are awaiting instructions from Toyota Corporate and cannot proceed independently.

My car accelerated very fast as I was attempting to pull into a parking spot. At first attempt brake did not work. Was able to avoid an accident. No sensors went off. Best described as an out of control amusement ride.

Description of Issue: I have experienced repeated incidents where the accelerator pedal becomes unresponsive (“dead pedal”) after coming to a stop. When pressing the pedal to accelerate, the vehicle does not respond at all for several seconds. Then, without warning, it suddenly surges forward with excessive acceleration once the power engages. This problem happens intermittently throughout a drive each day, often enough to be concerning. It occurs after being stopped at an intersection or in traffic. No warning lights or error messages appear before or during the issue. The delay followed by a sudden surge is dangerous, as I expect the car to move when I press the pedal, but it hesitates instead. When the vehicle finally responds, it accelerates quickly, which could cause me to lose control or collide with another vehicle. Safety Concern: This malfunction creates a significant safety risk. It puts myself, passengers, and other drivers in danger when the vehicle fails to accelerate as expected in high-risk scenarios such as crossing intersections, merging into traffic, or making left turns. The hesitation can leave the vehicle exposed in traffic, and the sudden lurch forward can cause unintended movement or rear-end collisions. Status: The problem has occurred multiple times under similar conditions and is ongoing. It has not yet been inspected or confirmed by a dealer or service center, but I have an apt Aug 24th. However, the malfunction is real, reproducible, and presents a serious hazard that could lead to an accident if not corrected. Many others with the same vehicle have expressed the same concern as well on forums and reported no fix after dealership appointments.

I've had consistent issues with the vehicle accelerating and shifting. These include sluggish acceleration, loss of power, sputtering, and limp mode. We've almost been hit by other vehicles almost 10 times because the vehicle has failed to accelerate when pulling into a roadway. The vehicle will start to accelerate slowly, then stop, then 5-10 seconds later will surge forward will the engine revs very high and is delayed shifting into 2nd gear. I've told my Toyota dealership about this numerous times but they keep telling me that there's no issue but there clearly is being that many others are experiencing the same exact problems. There's never been a warning lamp or message when this happens. This is a huge safety issue and my family is extremely lucky that we haven't been involved in a serious accident.

*Acceleration lag from a stop On June 21, 2025 - 92 degrees outside leaving store, I was making a left turn from a parking lot. I took my foot off the brake to creep forward which the vehicle did, but as I pressed the gas the car would not accelerate. I was stuck in the middle of the lanes with my car coasting. Fortunately it was a quiet street and the car coming from behind me had ample time to stop until i could coast my car to the side of the road which then it revved high and engaged. It felt like the car was in neutral but it was in drive. It lasted about 5 seconds. *It would not accelerate which was scary and very dangerous for obvious reasons. * I took the car to the dealership on the next business day and unfortunately cannot have it inspected until July 15, 2025. *No warning lamps, messages or other symptoms. *My car is available for inspection. That would be great! That’s why I brought it to the dealer but they were booked. *It happened only once, but I haven’t driven it much since the incident. I am now driving my 20 yr old, reliable MDX until I can get it inspected on July 15th

Engine failed to engage while trying to pull out of my neighborhood this morning. The electric motor starts and propels the car forward into the road, but the gas motor fails to engage leaving me in the middle of the road without the ability to maneuver. This is a recurring problem. The dealer is aware of it and I have made reports here before. Just documenting each time until Toyota cooperates and helps find a solution. The car does not display any error codes. When I call the dealership to tell them and hopefully go in to have them run a diagnostic they consistently fail to get back to me or downplay my concerns.

Car failed to accelerate when pulling into traffic on 5 lane road. Dealer completed a software update on 9/17 they thought would remedy the issue (which is ongoing) but it apparently did not. Vehicle gives no warning lights, error messages, etc. Just does not accelerate from a complete stop for 4-5 seconds.

Car will not accelerate immediately from a stop; seems to happen more often when on a slight incline. This poses a safety issue when pulling out onto any road. I have asked multiple times at the dealer about and been told they cannot do anything about it unless the car gives a code. They also say it will not reproduce for them, although every time I pull out of their service location (with a slight incline) it stalls out and will not engage immediately for me.

On high-temperature days, when the A/C is running at full capacity, the vehicle occasionally fails to accelerate from a stop. This issue persists even after applying the recommended ECM update. The lack of reliable acceleration poses a significant safety risk, particularly when turning across oncoming traffic or entering a busy street. This situation can leave the vehicle stalled in the path of approaching vehicles, increasing the likelihood of an accident.

I have now experienced 5 times in one month where my Toyota Grand Highlander Hybrid Max Platinum will not accelerate after breaking at a stop sign or stop light when the gas pedal is engaged.

When accelerating from a complete stop, there will occasionally be significant hesitation in the car actually accelerating. For example, I was at a stop sign then attempted to make a left turn when there was a break in the oncoming traffic. My car would not accelerate, almost as if it shut off. It then begins to accelerate. On another instance, I was at a stop sign and when I had the right of way, I stepped on the gas pedal but the car would not accelerate until roughly 10mph, at which time the acceleration kicked in. After this happened a few times, and after reading about it in social media groups, I brought the issue to the attention of the dealership. At the time of service, they were able to replicate the issue and performed a software update (T-SB-0017-24). That seemed to help but only for a few days, then the issue happened again - twice in the same afternoon. I took the car back, only to be told the issue could now not be replicated and that there was no additional fix. It happened again this morning. It is only a matter of time before I get broadsided because my car doesn't move through a turn or the intersection because it just rolls until the acceleration kicks in. I'm concerned about getting rear ended when the car doesn't move at the appropriate speed when either the light changes or from a stop at a stop sign. There are no warning lamps that appear or any sort of system malfunction notices.

Multiple times I have pressed the gas pedal and the car has not responded, as in did not accelerate. I was almost T-boned one time because of it since I was turning left and could not accelerate above 5mph. This is a frequent issue among GH Hybrids from talking to others.

- Vehicle intermittently will not respond or will barely respond when accelerator is depressed from a complete stop or near (rolling) stop. I have noticed this issue mainly when A/C is on high and during hot temperatures. I reside in the Phoenix, AZ area where high temperatures have been ranging around 110-115. - This poses a safety risk when attempting to pull out onto a busy road, either turning left or right. If the gas pedal fails to respond, this could lead to a serious crash. - This issue has arisen following a recent software update that Toyota performed (under service bulletin TSB-0017-24). This update was done to correct a different issue (shifting hesitation between gears when accelerating from 0-40mph), however it seems to have negatively affected the response of the vehicle when starting up from a stop. I have not yet taken my vehicle back to Toyota with this issue, but MANY owners of the HybridMAX are experiencing this same issue as the weather temperatures have peaked. - No warning lights appear when this occurs. The problem arose shortly after I had a software update done at the dealer on June 14, 2024.

**Vehicle:** Toyota Grand Highlander Hybrid Max **Issue:** On high-temperature days, when the A/C is running at full capacity, the vehicle occasionally fails to accelerate from a stop. This issue persists even after applying the recommended ECM update. **Safety Concern:** The lack of reliable acceleration poses a significant safety risk, particularly when turning across oncoming traffic or entering a busy street. This situation can leave the vehicle stalled in the path of approaching vehicles, increasing the likelihood of an accident. **Action Taken:** Applied the ECM update that is supposed to resolve the issue, but the problem persists.

1. Transmission issues with slippage, response. Issues where when going from reverse into drive taking 2-3 seconds to engage. Issues coming from a stop to going as well whereas there’s a hesitation with propulsion. 2. Safety has been at risk numerous times when pulling into heavily trafficked areas. Response to pedal should not have a 1-2 second hesitation, but it does and it’s sporadic. Can no longer back into locations where it may be important to put it into drive and move fast, a 3 second delay is a long time when you’re not moving and someone is going 50mph in a 35. 3. Dealer reproduced the delay from reverse to drive and annotated it was “normal” behavior. 4. Dealer denies issues with transmission, brought to another where they said it was a CVT and that’s just how they are and master tech came for drive with me. He was wrong, XLE is not a CVT. They flashed it/reset it. Seemed to help with shifting issues, however it did not fix delays. 5. No warning lamps.