KNOWN FAULTS · Hyundai

Hyundai Bayon 1.0 T-GDi / 48V common problems.

2021–2026 · Petrol

Sources are not verified in real time and no entry confirms that your car is affected.

4 known faults with sources

Applies if: Same type of direct-injection turbo engine (T-GDi).

Carbon on the injectors and intake of the T-GDi petrol enginesInjection / turbo

Engine / equipment: Hyundai and Kia 1.0 and 1.6 T-GDi direct-injection turbo petrol engines
Period mentioned: 2015 onwards
Symptoms: Loss of power, higher consumption, hesitation or rough idle, usually at high mileage.
Possible cause described: With direct injection, petrol does not wash the intake valves and carbon builds up on the injectors and intake. German guides mention it for the i20 III, Tucson IV and Picanto III (dirty injectors).
Check for the garage: Read misfire and fuel-trim codes; inspect the injectors and valves with a borescope; clean the intake if there are deposits.
Cost cited in the source: No verified estimate; ask the garage for a quote.A rough figure from the original database, not an up-to-date quote.

Applies if: The Bayon is based on the i20 III and shares its engines; confirm by VIN which campaigns apply.

Rattles, rear brakes and eCall on the i20 IIIKnown weak points

Engine / equipment: Hyundai i20 III (1.2, 1.0 T-GDI 48 V and 1.6 T-GDI N)
Period mentioned: 2020 onwards
Symptoms: Rattles on the driver and passenger sides, squeaks from the rear axle (rear brakes) and carbon on the T-GDIs at high mileage; on the naturally aspirated 1.2 the guide knows of no engine problems.
Possible cause described: A recall for limited eCall function on 2020 model-year cars. The guide says it is still too early to judge its reliability.
Check for the garage: Check the eCall campaign by VIN; check the rear brakes if they squeak.
Cost cited in the source: No verified estimate; ask the garage for a quote.A rough figure from the original database, not an up-to-date quote.

Applies if: Built from 1/4/2021 to 3/12/2022 (campaign 51DT0). Confirm by VIN.

Loss of power or no start because of the fuel pump (2021–2023 Hyundai i10, i20 and Bayon)Fuel system

Engine / equipment: Third-generation Hyundai i10, third-generation i20 and Bayon (petrol)
Period mentioned: 2021–2023
Symptoms: Loss of power, hesitation or an engine that will not start for lack of fuel; it can leave the car stranded unexpectedly.
Possible cause described: The fuel pump may have a manufacturing defect. Hyundai recalled the i20 and Bayon built from 1/4/2021 to 3/12/2022 (campaign 51DT0, about 180,000 cars worldwide, German KBA alert of July 2025) and the i10 built from 1/11/2021 to 25/4/2023 (about 89,000 cars, March 2026). In both cases the pump is replaced.
Check for the garage: Check by VIN with Hyundai whether your car is in the recall and whether it has been done; replacing the pump takes less than an hour. If it is not in the campaign, the garage measures fuel pressure and flow before replacing parts.
Cost cited in the source: Free under the recall.A rough figure from the original database, not an up-to-date quote.

Applies if: Only with the 7-speed dual-clutch automatic (7DCT). Confirm the gearbox type.

Judder on the 7-speed dual-clutch gearbox (7DCT)Automatic gearbox

Engine / equipment: 7-speed dry dual-clutch automatic (7DCT)
Period mentioned: Approx. 2015–2021
Symptoms: Abnormal vibration or shudder when pulling away and at low speed, especially in traffic.
Possible cause described: Dual-clutch behaviour at low speed; Hyundai and Kia issued technical bulletins with new gearbox software (anti-judder logic) and, if that is not enough, a clutch replacement.
Check for the garage: At the dealer: run the judder test with the diagnostic tool, install the latest gearbox software and replace the dual clutch only if the judder remains.
Cost cited in the source: No verified estimate; ask the garage for a quote.A rough figure from the original database, not an up-to-date quote.