2023 Hyundai Tucson: misfire or rough idle

Filed Oct 1, 2026 · Fuel system · MA

2023 Hyundai Tucson Limited, 2.5L GDI, Alabama-built (VIN 5NMXXXXXXXXXXXXXX), built [XXX]. On [XXX], at about 37,550 miles, the check engine light came on flashing and the engine ran rough while I was traveling in Canada. My scan tool showed P0300, P0302 and P0304 (misfires on cylinders 2 and 4). On July 6, 2026, Experience Hyundai in Charlottetown, PE (service order 92XXX) replaced one ignition coil under warranty. No fuel injector leak test was performed. The misfires returned. On [XXX], at 39,409 miles, my scan showed P0302 active and P0304 pending. The car also had extended cranking after sitting and the check engine light was on. I was told I could keep driving the car unless it started to jerk or engine light started to flash, then immediately stop driving it and have it towed. On September 25, 2026, the car was towed to McGovern Hyundai Route 2, Leominster, MA (invoice 148XXX). The dealer found all 4 fuel injectors leaking and replaced them under warranty with injector service kit 35399-2S133QQH. My vehicle is outside the production range of Hyundai TSBs 23-FL-002H-1 and 26-FL-001H, which cover this injector failure only for Alabama-built Tucsons produced through July 11, 2022. Yet it failed in the same way. I am concerned the defect extends beyond the bulletin dates and that a sudden misfire could cause loss of power in traffic. There is no recall for this condition. The dealer found all 4 fuel injectors leaking, even though only cylinders 2 and 4 had set misfire codes and replaced them under warranty with injector service kit 35399-2S133QQH. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Sep 9, 2026 · Fuel system · UT

The car was working perfectly fine I drive it for work all the time and one day it started shaking weirdly. A couple days later the check engine light turned on. It was throwing the code that was pointing to "misfiring in the 3rd cylinder" We changed all the spark plugs, 3rd cylinder coil pack, and switch the coil pack to see if it would say a misfiring in a different cylinder. We then took it to a mechanic saying that it is the high pressure fuel injectors and that he has seen this problem with other Hyundai Tucson around the same year as us and that there was a bulletin on it.

Filed Jul 8, 2026 · Acceleration, Engine · NC

I was on the highway on the way to work when my car started stalling. Every time I pressed the gas to give it some power, it would not go anyway where. after getting it towed to get looked at some of the fuel injectors failed and were misfiring. The warning message about ‘check engine’ popped up 2 minutes before it happened. this is the third time now in less than 6 months.

Filed Jan 28, 2026 · Engine, Fuel system · ME

All four cylinders misfired in my car while driving causing the catalytic converter and all four fuel injectors to need to be replaced. My car suddenly stopped driving in a rural area with only a few minutes of warning when the engine light came on. I was not even able to drive to a nearby shoulder. I was stranded on the side of the road in 5 degree weather until a tow truck could come.

Filed Jul 3, 2025 · Brakes, Engine · IN

Engine misfiring, causing low power on interstate 70 also losing brake control.

Filed Nov 30, 2024 · Fuel system · PA

(1) [XXX] (14,568 mi): The vehicle had been running normally. My wife was about to switch lanes at an intersection when the vehicle started to shake and vibrate. The entire dashboard lit up and the vehicle quickly died. She tried restarting it and the engine wouldn’t turn over. Anytime there was an attempt to restart, there was a potent odor of gasoline. The car died in the middle of the road. It would sort of start but then it wouldn't move and would just shake and smell of gas. After many minutes of trying to start the vehicle, barely got power but was able to pull to side of road around other cars. Hyundai app reported codes: P030300 and P217800. Had car towed to local dealer. Picked the car up and next day spoke to the service manager who indicated there was a 20%-25% chance this would reoccur. He said there was nothing he could do as Hyundai would only cover the cost for the existing issue. The paperwork from the dealer shows it was a P0303 for cylinder 3 misfire and system too rich caused by leaking fuel injector for cylinder 3 (low pressure). [XXX] (14,702 mi) I was driving the car, in middle of an intersection and the vehicle started to vibrate and all lights on dash lit up (check engine, battery, etc.) and smell of gasoline. Car hesitated and wouldn't move. Died in intersection. Had to have 2 people help push me as I was dead in middle of road with people beeping and passing me. Got to side of road and couldn't get vehicle to start. No error codes on app this time, but all symptoms were exactly the same. Called for tow, different dealership due to location. Dealership indicated they would return it to us safe, but because of Hyundai policies, they can only work on the affected items. This is well documented by Hyundai owners of this problem and going by what the service manager of the first location told me, this is common to spread to other injectors. THIS IS UNSAFE! TWICE IN MIDDLE OF INTERSECTIONS! TWO MORE INJECTORS! SOMEONE IS GOING TO GET HURT! INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFO

Filed Feb 27, 2024 · Engine · 15,000 miles · SC

The contact owns a 2023 Hyundai Tucson. The contact stated that while driving approximately 40 MHP, the vehicle suddenly lost motive power and stalled. The vehicle was towed to the local dealer who diagnosed an engine misfire in cylinder #3. The cylinder #3 was replaced and the vehicle was repaired. The vehicle later experienced the same failure and was towed to the dealer who diagnosed that cylinder #4 was faulty. The cylinder #4 was replaced and the vehicle was repaired. The contact stated that the manufacturer had issued a TSB for the failure that included all four cylinders were faulty. The failure mileage was 15,000.