2021 Hyundai Tucson — Known Issues & Recalls

While driving your 2021 Hyundai Tucson at 10 mph, you heard an abnormal clicking sound from under the hood with no warning lights. You pulled over and noticed white smoke leaking from under the hood that turned black and increased in intensity, leading to a fire that required the fire department to extinguish it. The vehicle was consumed by the fire and deemed a total loss at approximately 65,000 miles. The exact cause of the fire was not identified, and the vehicle was never diagnosed or repaired.

Your engine has been consuming oil excessively over the past 3+ years, requiring frequent top-ups. The dealer eventually confirmed the engine needs to be replaced, but is now denying the warranty claim despite their earlier assessment. You've been without your car for 2 weeks with no loaner vehicle provided.

Your engine stopped running on the highway just 3 days after an oil change, with no warning light beforehand. The dealership previously found your engine had no oil despite your regular maintenance schedule, performed an oil consumption test, and then denied warranty coverage. Your engine appears to be consuming oil abnormally, which may require the engine to be replaced or rebuilt.

Your engine started making a knocking sound that got louder as you accelerated, then your oil pressure warning light and check engine light came on. Your car began accelerating and decelerating on its own, forcing you to pull over across multiple lanes on the highway. This matches a known issue Hyundai has documented. The fix will likely require engine inspection, oil analysis, or possibly engine replacement depending on what's causing the low oil pressure.

Your 2021 Hyundai Tucson has stalled and lost power three times while driving in just 55 days of ownership, creating a serious safety hazard. Each time, the engine light flashed, RPMs spiked, and the car entered a severely limited mode where it couldn't exceed 3,000 RPM or 50 MPH—most dangerously during highway merging and on a busy road 300 miles from home. The dealer has refused to replace the engine despite the vehicle's extended warranty and service records showing prior engine problems. Diagnosing and repairing this issue will likely require engine inspection, connecting rod bearing replacement, or full engine replacement.

Your engine is consuming oil abnormally, and you've already replaced three catalytic converters by 31,000 miles. Recently, your car started shaking, and the ignition coil and spark plugs were found to be faulty. Even though an oil consumption test passed, these repeated failures suggest an underlying engine problem that keeps damaging multiple components. The fix will likely involve a thorough engine diagnosis to identify what's causing the excessive wear on catalytic converters, ignition coils, and spark plugs.

Your 2021 Hyundai Tucson suddenly lost power while driving on the freeway and went into limp mode, forcing you to pull over safely. The check engine light is flashing, and a diagnostic scan found error code P1326, which Pep Boys flagged as requiring immediate attention. Your vehicle won't safely reach freeway speeds in its current condition. The issue may require engine sensor replacement or ignition coil service, depending on what the dealership finds when they investigate code P1326.

Your engine is consuming more oil than normal between service intervals. You may need to add oil more frequently than expected, or you might notice low oil level warnings on your dashboard. This could indicate internal engine wear or a leak that needs diagnosis, and may require engine inspection or seal replacement.

Your oil warning light comes on about 1,500 miles before your scheduled oil change, and the dipstick shows no oil even though you keep adding more. You're having to top off the oil repeatedly between service intervals, which could lead to engine damage if not addressed. Your dealer should inspect the engine for an oil leak or faulty oil level sensor.

While driving, your check engine light began flashing and your engine started bucking or jerking. Despite regular maintenance with documented oil changes, Hyundai has refused to cover the issue under warranty, citing that this is a known problem affecting 2021 Hyundai Tucsons. A mechanic will need to diagnose the engine fault code and address the underlying cause of the bucking.

While driving at 70 mph, your engine warning light started blinking on and off, and your car's power was reduced, limiting your speed to 60 mph. This is typically a sign that your engine's computer detected a problem and entered a safety mode to protect the engine. You should have the diagnostic trouble codes read with a scanner to identify the underlying issue.

Your Tucson went into limp mode (severely limiting engine power) multiple times within days of purchase, forcing the vehicle to slow down to 7 MPH while driving at highway speed. The dealer replaced the NOX sensor three times and the catalytic converter, but the problem kept returning. This repeated failure suggests a serious issue with the emissions control system that wasn't fully resolved by the repairs attempted.

Your check engine light keeps coming on while you're driving at different speeds. Multiple mechanics have found that your engine is burning through oil much faster than normal, and your dealer says the engine needs to be replaced. You're at about 89,000 miles and the manufacturer hasn't offered to help with the repair. The fix will require a complete engine replacement, which is a major repair.

While using your defroster with the air conditioning on, you noticed a metallic smell. Your rear windshield then suddenly cracked and shattered. You saw smoke coming from the vehicle, and when you looked in the rear-view mirror, you saw fire in the trunk. You safely pulled over, turned off the engine, and called 911. The fire department will need to investigate the source of the fire, which may involve inspecting the trunk electrical system, battery connections, and wiring.

Your rear hatch window suddenly shattered into pieces while you were parking in an underground garage after driving 41 miles in below-zero temperatures. You heard a loud pop just before the glass imploded inward. This happened without any collision or impact to the vehicle.

Your sunroof suddenly collapsed inward while you were driving on the freeway, scattering glass throughout the vehicle without any warning or apparent cause. You experienced pain and ear ringing from the incident, and no external impact or extreme temperature conditions preceded the failure. This issue requires investigation into potential defects in the sunroof panel or its mounting system.

Your 2021 Tucson's catalytic converter was diagnosed as faulty in January 2025, but the dealership didn't replace it and sent your car back without fixing the problem. Less than a year later, your vehicle developed recurring emissions failures, loss of power, and drivability issues with warning lights repeatedly coming on. The manufacturer is now refusing to replace the catalytic converter and blaming oil consumption instead, leaving your car out of service. Getting this fixed will likely require replacing the catalytic converter, oxygen sensors, and spark plugs, plus addressing the underlying emissions system problem.

When you brake at low speeds, your car makes a hissing or buzzing noise and the brake pedal feels soft, happening more frequently as mileage increases. The dealership replaced a tone ring but the problem persists—you've noted the symptom is different from normal ABS activation and no warning lights appear. A repair shop will need to diagnose the actual cause, as it may involve the ABS system, brake pressure sensors, or related electrical components.

Your engine is making a knocking sound and a warning light has come on. You're also noticing that your car accelerates and decelerates on its own without you controlling the pedal. Your dealership has suggested a complete engine replacement but hasn't provided a detailed diagnosis of what's actually wrong. Addressing this will likely require engine diagnostics to identify the root cause, which could involve anything from spark plugs and ignition coils to fuel injectors or internal engine components.

While driving on a highway, your car entered a reduced-power mode that limited your speed to around 60 mph, causing it to slow down and then speed back up repeatedly. Your check engine light was blinking (not steady), which indicates an engine fault. The issue likely requires a diagnostic scan to identify the underlying engine or transmission problem causing the limp mode.