2017 Toyota Highlander: misfire or rough idle

Filed Jun 3, 2026 · Engine · 151,000 miles · TX

The contact owns a 2017 Toyota Highlander. The contact stated that while driving at an undisclosed speed, the check engine warning light illuminated. The vehicle was taken to the dealer, who determined that the spark plugs needed replaced. The spark plugs were replaced by an independent mechanic, but the failure recurred. The vehicle was taken back to the independent mechanic, who retrieved diagnostic trouble codes P11F0 (Air-Fuel Ratio Imbalance) and P0305 (Misfire In Cylinder Number 5). The mechanic cleaned the fuel injectors, but the failure persisted. The contact was informed that the fuel injectors needed to be replaced. The vehicle was taken to a second dealer, Toyota of Cedar Park (5600 183A Toll Rd, Leander, TX 78641), who determined that cylinder #5 needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 151,000.

Filed Aug 27, 2025 · Fuel system · UT

Today (8/26/2025) my wife experienced the engine light kicked on and that the AWD system needed to be checked. After fueling up it made knocking noises and difficulty starting, and took two times to start up. Ran an OBD scan and this is what it says, which is related to fuel pump low pressure. P117B - Fuel Pressure Sensor Circuit Range/Performance Severity - High Description - Indicates a problem with the fuel pressure sensor circuit, where the sensor's output signal is outside the expected range or performance criteria, leading to potential issues with fuel delivery or engine performance. P0174 - System Too Lean (Bank 2) Severity - High Description - Your engine is getting too much air and/or not enough fuel, this is known as a "Lean" condition. Excess oxygen is getting into your engine, which makes the combustion process less efficient. This could be caused by many different factors. Consequences of Continued Driving - Reduced power, Engine knocking, Rough idle

Filed Jun 19, 2025 · Electrical · NJ

Car is shaking heavily when stopped. Several misfires while engaging the brakes. Mechanic is telling me that he has seen many vehicles of this model with faulty purge valves.

Filed May 29, 2024 · Electrical, Engine · NY

While accelerating onto highways, my Toyota Highlander suddenly misfires, causing rough engine and a natural response to decelerate instead of continuing to accelerate. The ignition coil was blamed, I replace and then a week later it happens again while trying to accelerate on the highway. Another replacement and then it happens again a third time. There was a known issue under Toyota’s TSB 0148-19, where engine computers were reprogrammed and all coils replaced. My vehicle model year and engine model but doesn’t show this TSB. I am aware TSBs are not recalls, but the sudden repeat engine misfires, all in a year, while accelerating to highway speeds, is a concern.

Filed Jan 31, 2021 · Brakes, Engine · 48,939 miles · CA

I had this car 2017 brand new, after 10000 mile, I heard some noises for my front wheels, I did my oil and maintance service often by toyota dealership,I told them all the time about brakes and front wheel make some noises, they always everythings looks fine, after 2 yrs I had engine check lights on, I went to toyota dealership, and they sayed it s not covered I have pay my own money for fixed, they sayed engine misfire on cylinder, for new car only driving 2yrs, it s happened feb/05/2019, after 6 months they found front passenger outer cv boot leaking and I have to pay my own packet too, and now I have again problem , when I am driving on freeway about 70 mgh I heard some noise on my car back seats down, when I looked under my car there is no crack or leaking, looks everything good, I dont know where is noices comming from my under car, I just went to maintence today again toyota dealership they sayed everythings normal, I dont know now what should I do, I am not really happy with my new car and with toyota

Filed Sep 22, 2020 · Acceleration, Transmission · 42,000 miles · PA

On 3 separate occasions at 30,000, 40,000 and 42,000 miles when driving at interstate highway speeds (around 70 MPH) with cruise control engaged, the vehicle has suddenly without warning switched to a low power limp home mode resulting in rapid deceleration in the midst of high speed highway traffic. I believe this is a very dangerous situation. Multiple warnings appeared on the dash including low power mode, check awd system, and see your dealer. Shutting off the vehicle and restarting it allowed the vehicle to be driven normally again. After all three incidents the vehicle was taken to the dealer for diagnosis. All 3 times the computer had stored codes for random multiple misfires along with a few others. All three times the dealer indicated that the codes did not point to a specific faulty part that they could replace, so there was nothing they could do. At my insistence that something be done after the third incident the dealer opened a case with the toyota tas system to ask for assistance in diagnoses. The only result of this was to switch some of the coil pack positions to see if the misfires followed the coil pack. The end result is that I have to drive it until it fails again, putting myself and others at risk. I also opened a case with the toyota customer experience center, they confirmed this was all toyota would do at this point.