Hyundai Kona

The EGR system on the 1.6 CRDi D4FE is prone to soot deposits in urban use. Cleaning the EGR valve and intake manifold is recommended to prevent swirl flap breakage.

Symptoms: Power loss, rough running, check engine light, EGR fault codes (P0400–P0409).

The diesel particulate filter of the Smartstream D4FE does not fully regenerate in predominantly short-trip use. The engine enters limp mode; complete DPF cleaning or replacement becomes necessary.

Symptoms: Limited engine output (limp mode, max. 3,000 rpm), check engine light, DPF warning indicator, unpleasant smell after failed regeneration.

The variable turbine geometry (VTG) of the Smartstream turbocharger tends to stick with carbon build-up. Vehicle enters limp mode; sometimes only cleaning is needed, sometimes the turbo must be replaced.

Symptoms: Sudden power loss, limp mode, irregular turbo response depending on driving situation.

D4FE injectors are prone to uneven spray patterns and leaks at the copper sealing washers. Diesel can enter the oil (oil dilution), compromising lubrication.

Symptoms: Hesitation on acceleration, difficult cold start, rising oil level without topping up, fuel smell in engine oil.

The EGR valve on the D4FE is prone to heavy soot deposits, causing rough running, increased fuel consumption and DPF problems. The situation worsens significantly with short-trip use.

Symptoms: Rough idle, power loss, increased consumption, DPF warning light

Piezo injectors on the D4FE can weaken: fuel rail pressure builds only slowly on start attempts (50–80 bar instead of 140 bar), causing difficult cold start and power drops.

Symptoms: Engine starts poorly, starter cranks for a long time, pump needs to be primed several times

The D4FE's DPF clogs prematurely in predominantly short-trip use. Regeneration cycles can multiply when the EGR valve is stuck; replacement costs up to €2,400.

Symptoms: DPF warning light, frequent regeneration, power reduction, increased consumption

Kona models from 2018 were recalled due to an electrical short circuit with fire hazard. Check recall status before purchase.

Some Kona EV examples show unusually rapid battery capacity loss or brief failures. Hyundai initially capped charging capacity at 90%; affected vehicles received new batteries.

Vehicles from 2018–2020 with LG Energy Storage cells were recalled due to elevated short-circuit and fire risk. Over 77,000 vehicles worldwide affected; fire risk exists even while parked with a fully charged battery.

Kona OS models from 2020 are affected by a recall because the emergency call system (eCall) does not transmit the vehicle identification number correctly when the airbag deploys. Software update resolves the issue.