2015 Toyota Highlander engine problems

Filed Oct 29, 2026 · Engine · CA

My 2015 Toyota Highlander equipped with the 3.5L V6 engine developed an engine oil leak originating from the timing chain cover sealing area. On April 30, 2026, Kearny Mesa Toyota in San Diego, California, identified the leak during an inspection when the vehicle had a little over 100,000 miles. I am concerned that this condition may indicate premature failure of the timing chain cover sealing system and warrant investigation into a potential design or manufacturing defect. An engine sealing system should be sufficiently durable to prevent oil leakage under normal operating conditions. The occurrence of this problem at just over 100,000 miles raises concerns about the long-term reliability of this component and whether similar failures affect other vehicles equipped with the same engine. Although the leak was described as seepage or oily residue, it may worsen over time. Depending on its severity and location, leaking oil could contact hot engine or exhaust components, potentially causing smoke or creating a fire hazard. Continued oil loss could also compromise engine lubrication, lead to significant engine damage, or result in unexpected vehicle failure. These are potential safety risks associated with the condition, not claims that a fire or engine failure has already occurred. The oil leak was identified by a Toyota dealership during an inspection. The dealership’s diagnosis and related service records may be available for review upon request. Whether the manufacturer has formally investigated or acknowledged this condition as a defect is unknown. I respectfully request that the federal safety agency review this complaint alongside other reports involving timing chain cover oil leaks in 2015 Toyota Highlanders equipped with the 3.5L V6 engine. I ask the agency to determine whether these reports indicate a recurring premature component failure, whether the condition presents an unreasonable safety risk, and whether further investigation or corrective action is warranted.

Filed Aug 27, 2026 · Electrical, Engine · TN

The a/c condenser was damaged due to impact of road debris. This caused loss of proper system operation. The cost to repair was $1100+. The debris entered thru the front grill, which has nothing in place to prevent debris from entering the engine compartment.

Filed Dec 12, 2024 · Acceleration, Engine · NC

Driving to take my son to work. Check engine light came on said check and system. Hard shifting put in manual drive and made it to destination.

Filed Sep 26, 2024 · Electrical, Engine · 193,000 miles · AL

The contact owns a 2015 Toyota Highlander. The contact stated while driving 65 MPH, the vehicle stalled, and the steering wheel became difficult to turn. The check engine warning light and several other unknown warning lights were illuminated. The contact was able to pull into a parking lot. The contact was able to restart the vehicle after 45 minutes. The vehicle was taken to an independent mechanic, but the vehicle was not diagnosed or repaired. The dealer was notified of the failure and charged a fee for diagnostic testing. The contact related the failure to the federal safety agency Campaign Number: 18E107000 (Electrical System, Visibility); however, the VIN was not included. The manufacturer was not notified of the failure. The failure mileage was approximately 193,000.

Filed Jul 21, 2024 · Engine · PA · fire

SPONTANEOUS VEHICLE FIRE: While driving approximately 20-30 miles per hour, with no other symptoms or advance warning signs, a message suddenly appeared on the dashboard saying "Engine Failure - Turn off Ignition". The temperature gauge was firmly in the normal range; the car had been inspected a few months prior, and had recently had routine maintenance. There was no indication that anything was amiss before this incident. 30 seconds after the sudden warning message appeared, smoke began pouring from the hood and I immediately pulled over to the side of the road and exited the vehicle with my young daughter. The smoke continued and the entire front section of the vehicle quickly caught ablaze. Police and the fire department arrived on the scene to assist and extinguish the fire. The vehicle was towed and determined to be a total loss by insurance. Our safety was put at risk because our vehicle spontaneously caught fire with no early warning signs; if we had been driving on a highway or a road without space to quickly stop the vehicle and safely exit, we would have certainly faced injury or possible death given the speed and ferocity with which the fire erupted. After we contacted Toyota several times, they sent an inspector to look at the vehicle, and reported: "The inspector observed extensive fire damage to the engine compartment and interior of the vehicle. The inspector also observed that there was no oil registered on the dipstick. There were no arc marks on the wiring in the engine compartment when inspected. The inspector did not observe any oil leaks when inspected. The battery hold down bracket was in the proper location. The cause of the fire was undetermined, and there was no evidence from the inspection to indicate that this incident was a result of a vehicle defect." Toyota has shown a complete lack of curiousity as to determining what could have caused the fire and has only focused on avoiding liability, thereby putting customer safety at risk.

Filed Jul 26, 2023 · Electrical, Engine · IL

I experienced a sudden engine failure while driving my 2015 Toyota Highlander on Interstate 294 outside Chicago. I was driving about 75 mph in the far left lane. A warning message "Check AWD" came on the screen, followed by the Engine icon lighting up, then a "TRAC off" message appeared on the screen. I began to merge to the right across four lanes of traffic to get to the shoulder. As I was doing so, a beep sounded, and the message "Engine Stopping" appeared on the screen. The accelerator stopped working. I reached the shoulder and the car came to a stop just as I made it to the shoulder. The whole incident, from the time the first warning light came on until the car completely stopped, lasted about three minutes. Prior to this, there were no warning lights, and I had been driving the car without incident. The car had received all regular maintenance at proper intervals. Mileage was 86,100 at the time. There were five people in the car, including myself, my teenage daughter, her friend, and her friend's parents. We were driving the girls home from a summer camp. We are unharmed -- and possibly alive -- only because I was able to merge across four lanes of traffic and reach the shoulder before the engine completely failed. Just behind us and just ahead of us on this stretch of interstate, there is no shoulder. Semi trucks populate this very busy road. We had to sit on the shoulder for two hours waiting for a tow truck. We are all truly fortunate to be alive and unharmed. The vehicle is in the possession of [XXX] Toyota, [XXX] . The service department has diagnosed as follows: "Performed diagnostic and found codes P0300, P0301, P0302, P0303, P0306 engine misfire codes. Code P1603 Engine stalls out. P1604 Stability malfunction. Code P1605 Rough idle. Spark plug number 6 is damaged. Check piston with borescope, piston is also damaged." I am being advised to replace the engine at a cost of $8820. Toyota US has been notified. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5

Filed Oct 1, 2020 · Engine · 80,000 miles · MA

Tl* the contact owns a 2015 toyota highlander. The contact stated while driving approximately 55 MPH, the check engine warning light illuminated and the vehicle loss motive power and failed to accelerate as needed. The contact indicated that the vehicle failed to accelerate above 10 MPH. The vehicle was taken to toyota of braintree located at 210 union st, braintree, ma 02184, and diagnosed with a defective engine. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The approximate failure mileage was 80,000. The VIN was not available.

Filed Sep 25, 2020 · Engine · IL

Vehicle is burning excessive amounts of oil.

Filed Feb 6, 2019 · Electrical, Engine · 32,673 miles · SC

For two years now, my vehicle will randomly have an engine stall while operating the vehicle. It happens at different speeds and while going straight ahead or turning. The entire instrument panel and navigation screens shuts off and turns back on. I have taken the car in to toyota twice and was told they couldn't find anything wrong or get the the vehicle to malfunction again. Today, the engine didn't immediately come back on after stalling, and I had to pull over and turn the car off and back on again. My car has less than 33000 miles on it and has had regular maintenance. This is truly a safety concern at this point and it seems I'm not the only one with this issue according to those reported to the federal safety agency.

Filed Nov 20, 2018 · Acceleration, Engine · 66,670 miles · MA

When driving my highlander the following error messages appeared, error keeping the start button pressed will cause an emergency stop. I dismissed this. Then it popped up a message that car cannot drive while brake and accelerator are pressed simultaneously. I lost ability to accelerate so tried to pull of busy road, pressing the brake pedal restored acceleration. Then when I stopped in traffic or at lights the car shut itself down and had to be restarted. These error messages kept coming on while I drove to the dealer. I switched off the car at the shop and it wouldnt repeat the problem, no codes have been recorded by the vehicles computer because the check engine light never came on. Toyota and the dealership want to wait until it happens again. Since it happened before, also while it was driving I am uncomfortable as it is a safety concern. I don't want it to happen on a busy highway. I believe the intelligent power module of the car is shorting out and causing the car to go into failsafe mode and shut down creating hazardous driving conditions.