🇩🇪 Deutsch

Hyundai Tucson

G4KN 2.5L SmartStream 187 hp Automatic 2020–2024
✖ Stay Away!
Engine G4KN ✖ Stay Away! 6,500–20,350 €

Modern NA with high efficiency. Smartstream tech delivers low consumption while keeping adequate performance on tap.

Fun Factor? Decent

Modern SUV, comfort over thrills

The most polished Tucson yet — comfortable and modern, but dynamic fireworks are not on the menu.

Engine Weaknesses 5

!! Excessive Oil Consumption from Piston Rings

The Smartstream 2.5 piston rings have by design increased ring gaps. This results in high blow-by and oil consumption of up to 1 L/1,000 km. Hyundai acknowledged the design issue.

Symptoms: Dropping oil level between changes, blue exhaust smoke clouds, oil consumption above 1 quart per 1,000 miles.

1,500–4,500 € from 50,000 km
!! Turbocharger Oil Starvation from Extended Service Intervals

Extended oil change intervals cause lacquer formation in the turbocharger oil supply line. Bearings run dry and turbine shaft play develops.

Symptoms: High-pitched whine from the turbocharger, boost pressure drop, blue exhaust smoke, oil consumption.

2,000–4,000 € from 80,000 km
!! Oversized Piston Ring Gap Causes Oil Consumption

The G4KN uses piston rings with twice the clearance of older engines to reduce friction. This design leads to measurable oil consumption of up to 1 quart per 1,600 km in many vehicles.

Symptoms: Dropping oil level between changes, slight blue smoke, oil smell from exhaust, occasional stumble.

800–3,000 € from 30,000 km
!! GDi Valve Carbon Buildup

GDi direct injection leaves soot deposits on the intake valves, worsened by blow-by from worn piston rings. Early cleaning is strongly recommended.

Symptoms: Rough idle, misfires, cold-start power dip, P030x fault codes.

350–800 € from 50,000 km
!! Fuel-Oil Dilution from GDI/MPI Mode Switching

The G4KN's dual MPI/GDI injection system switches modes depending on load. In cold operation with GDI mode active, fuel can condense on cylinder walls and dilute the oil.

Symptoms: Rising oil level (fuel smell), thin oil on the dipstick, increased fuel consumption, mild stumble.

100–500 € from 20,000 km

Vehicle Weaknesses 9

!! Other Recall: brake servo can fail

The Tucson NX4 was subject to a recall due to possible failure of the brake servo. Affected vehicles must be checked by the dealer and repaired if necessary.

0–0 €
!! Other Recall: airbag installation error

Around 200 Tucson NX4 had to visit the workshop due to faulty airbag installation. The hybrid control unit was also updated with software on a further approximately 4,000 vehicles due to limited immobiliser functionality.

0–0 €
! Electronics Infotainment system freezes and crashes

The large infotainment system of the NX4 freezes regularly or restarts. Software updates from the dealer can help, but the problem is widespread.

0–200 € from 20,000 km
! Gearbox Dual-clutch transmission judders when setting off

The DCT in the NX4 shows slight juddering in some driving situations, especially when setting off on a hill or in stop-and-go traffic.

500–2,500 € from 50,000 km
! Electronics 48-volt system and start-stop faults

The 48-volt electrical system in early Tucson NX4 examples generates fault messages without a stored diagnostic code. Start-stop switches off uncontrollably, starter responds with a delay.

300–1,200 € from 30,000 km
! Electronics Condensation in headlights

Tucson NX4 headlights show condensation moisture inside, which impairs visibility quality and can damage the LED units over time. Warranty replacement is generally straightforward.

400–1,200 € from 20,000 km
! Interior Rattling interior trim panels

Several Tucson NX4 owners report rattling interior panels and poorly fitting wheel arch covers appearing shortly after delivery. Dealer correction is usually uncomplicated.

0–150 € from 10,000 km
! HVAC Poor cabin heating in cold weather

Tucson NX4 owners report insufficient heating performance at sub-zero temperatures. Engine stays below 50°C operating temperature, resulting in increased fuel consumption and inadequate cabin temperature.

150–500 €
! Electronics 48-volt system malfunctions

The mild hybrid 48-volt network shows sporadic fault messages and causes start-stop system failure. Several owners report complete power shutdowns while driving and necessary control unit resets.

400–1,800 € from 30,000 km

Reports & Tests

nhtsa_complaints NHTSA Complaint Summary 2026-03
Below Average

934 owner complaints filed with NHTSA (2020–2026). Most reported: Engine (231), Collision Avoidance (188), Other (172).