2023 Toyota Highlander Engine Problems

Issues with vehicle accelerating, bucking and hesitating

The vehicle surges and hesitates when pressing on the gas. Several times I push on the gas and nothing really happens. Slow to move. Other times I push on the gas and it “bucks”. Like the turbo kicked in to max power all of a sudden. Almost lost control of the car a couple times. Once was on a mountain road. I am hesitant to drive it and even more so to let anyone else drive it. For fear of them losing control and running off the road because it becomes impossible to handle for a split second. The entire time I’m driving, it sputters/hesitates. Something is wrong with the car. I will attempt to take it to the dealer, as I have less than 12,000 miles on it. But I’m not optimistic based on the threads I’ve searched on line. Seems like Toyota knows there’s an issue and hasn’t done anything to rectify it.

Engine intermittently has no power on take off and causes an unsafe condition to turning into traffic where car will just not go until after flooring it and a 3-5 second delay!! Engine also looses power and bucks or misses while accelerating through gears. This has caused multiple near miss incidents when turning into or across traffic. Also have issues with the steering assist that it yanks the wheel intermittantly. This cause me to loose control on the wet interstate in a turn when it yanked the wheel to the right while banking left at 65mph. I panicked and pulled the wheel back which cause a skid. The system has been turned off since. Toyota is not doing anything to repair anything and keep giving me the car back saying its fine.

Vehicle hesitates when accelerating. Very noticable when accelerating from stop. Also when passing a vehicle and accelerating to pass there is hesitation and the vehicle stutters at times also.

Sudden engine coolant temperature high warning comes on. Temperature jumps from normal to maximum on gage. Needle hunts from normal to high. Sometimes needle stays at high. Outside air temperature was 97 degrees Fahrenheit. Similar incident happened on 7/5/2023 when temperature was in the 90s.. Toyota dealer could find nothing wrong with the vehicle. This time I took a picture of the panel with the warning showing.

Pulled out of intersection and vehicle hesitated and surged upon acceleration causing bear miss from oncoming traffic vehicle consistently hesitates and surges from stop to 35-40 mph

I've had the car for 6 months. After a few months we noticed a "bucking" during acceleration and a "hesitation" when pressing the accelerator. Under medium to hard acceleration the car will exhibit these traits almost consistantly and now after 3500 miles it has become so noticeable that it is dangerous! The hesitation is "off the line" from a dead stop. There is at least a couple second delay sometimes when leaving a stop. And then as the car climbs in RPM's you can feel the engine struggling almost like a car with bad spark plug wires. It tends to "spit and buck" as it is accelerating. We have tried different fuels, fuel cleaners, different octanes, and nothing seems to curb the problem. We took the car to our local dealer and they confirm the problem but have stated that there is nothing they can do as it appears to be a software issue with the car. I have requested from Toyota using their "Brand engagement center" to provide an engineer to evaluate the car and so far have not heard back from them in almost a week.

When I hit the gas the car doesn’t go anywhere and almost got into an accident. Turbo lag maybe or something really really wrong. This is going to cause a huge accident

The "turbo lag" as the dealership calls it is horrendous. Vehicle has extremely poor acceleration from a stop. It is very dangerous when pulling out into traffic as acceleration falls flat for a second or two until it eventually responds and accelerates. I try to be very cognizant of the poor performance of the vehicle, but I feel it is a matter of time until something bad happens. I took the vehicle to the dealership and was told the vehicle drives as designed. Since there are no faults, the dealership has washed their hands. Contacted Toyota HQ and open a case but was told "sorry we do not have anything to offer". The complaints are all over the internet from a simple Google search and I believe Toyota will eventually release updated software as this really negatively impacts the performance of a 50K vehicle. Right now they seem to be in a state of denial and I am really disappointed.

The vehicle hesitates and stutters upon light to moderate acceleration. This can happen either from a dead stop or while moving in traffic. The concern was present when vehicle was purchased new in Feb 2023. Initially the dealership thought the symptoms were related to the transmission learning algorithm, but this was later determined not to be the case and the dealership was able to reproduce the drivability concern. The dealership was also advised that running 91 octane fuel eliminated the symptoms, however the engine is designed to run on 87 octane. Subsequently, the dealership was advised by Toyota to replace several parts associated with the VVT (variable valve timing) on the exhaust camshaft which did not resolve the concern. Toyota subsequently agreed to replace the vehicle after filing a lemon law complaint with NCDS. This drivability concern is a safety concern as the hesitation and stutter could occur during a traffic maneuver and cause an accident due to the engine not properly responding to driver input. No check engine or other warning lamps present when this occurs, which is most of the time though more pronounced when ambient temperatures are above 75F degrees.