Carbon build up on the 1.0 T-GDi
- Typically appears
- 50,000+ miles
- What to inspect
- Cold start and check idle quality

A 2021 Hyundai Bayon is now 5 years old, so an average example has covered around 67,500 miles. This is the first model year of the generation · early-build cars carry the highest share of teething faults and the most recall activity, so check the service history for completed recall work. Check the state safety inspection and service history alongside the documented faults below, which are sorted by whether a 2021 car has usually reached the mileage where they appear.
Compiled & reviewed by the VehicleFaults Research Team
The 2021 Hyundai Bayon is 5 years old, so an average example has covered roughly 67,500 miles. At that mileage 2 of the documented faults are already due, so check those first.
Documented onset mileage is at or below the ~68k miles an average 2021 car has covered.
Carbon build up on the 1.0 T-GDi
Trim wear on hire and lease returns
Age, electronics and build-related issues that are not mileage-driven.
Infotainment and camera faults
Rear disc corrosion on low mileage cars
Generate a tickable pre-purchase checklist for this exact year, mileage and variant · add photos and notes as you inspect.
Check this exact carYes, very low fault rate so far.
Five years transferable, which helps resale.
Interior plastics rather than mechanicals.