The Hyundai G4KJ is a 1,591 cc, inline‑four naturally aspirated petrol engine produced between 2015 and 2021. It features double overhead camshafts (DOHC), 16 valves, and sequential multi‑point fuel injection. In standard form it delivered 94–95 kW (128–129 PS) with torque between 156–157 Nm, offering responsive urban performance and smooth highway cruising.
Fitted to models such as the i20 (PB), i30 (FD/HD), and Venue (SU2), the G4KJ was engineered for fuel efficiency, low emissions, and everyday drivability in compact and subcompact applications. Emissions compliance was achieved through a closed‑loop fuel system, three‑way catalytic converter, and electronic throttle control, meeting Euro 6 standards across all production years.
One documented concern is premature wear of the exhaust camshaft lobe in early production units, referenced in Hyundai Technical Service Bulletin TSB‑ENG‑112. This issue stems from marginal surface hardening during manufacturing and is exacerbated by infrequent oil changes or extended high‑RPM operation. From mid‑2017 onward, Hyundai implemented revised camshaft metallurgy and updated valve spring retainers to resolve the defect.
Hyundai
All production years (2015–2021) meet Euro 6 emissions standards (VCA UK Type Approval #VCA/EMS/9215).
The Hyundai G4KJ is a 1,591 cc inline‑four naturally aspirated petrol engine engineered for compact hatchbacks and SUVs (2015–2021). It combines DOHC architecture with sequential multi‑point fuel injection to deliver linear power delivery and urban efficiency. Designed to meet Euro 6 emissions standards, it balances everyday drivability with low environmental impact.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,591 cc | |
| Fuel type | Petrol (Unleaded) | |
| Configuration | Inline‑4, DOHC, 16‑valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 77.0 mm × 85.4 mm | |
| Power output | 94–95 kW (128–129 PS) @ 6,200 rpm | |
| Torque | 156–157 Nm @ 4,500 rpm | |
| Fuel system | Sequential multi‑point fuel injection (MPFI) | |
| Emissions standard | Euro 6 | |
| Compression ratio | 10.5:1 | |
| Cooling system | Water‑cooled | |
| Turbocharger | None | |
| Timing system | Chain (maintenance‑free design) | |
| Oil type | Hyundai SP 5W‑30 (API SN/ILSAC GF‑5) | |
| Dry weight | 108 kg |
The DOHC layout provides smooth and linear power delivery ideal for city and motorway use but requires consistent oil changes every 10,000 km to prevent camshaft lobe wear, especially in early units (pre-06/2017). Hyundai SP 5W‑30 oil (API SN/ILSAC GF‑5) is critical due to its additive package supporting valve train durability. The engine uses a maintenance-free timing chain, but oil degradation accelerates wear on cam followers under high load. Fuel must meet EN 228 standards; ethanol blends above E10 may degrade injector seals over time. Revised camshafts from mid-2017 onward resolve the lobe wear issue per TSB‑ENG‑112.
Oil Specs: Requires Hyundai SP 5W‑30 (API SN/ILSAC GF‑5) (Hyundai Owner’s Manual PB/FD/HD/SU2). ACEA A5/B5 oils are not recommended.
Emissions: Euro 6 certification applies to all G4KJ production years (2015–2021) (VCA Type Approval #VCA/EMS/9215). No Euro 5 variants exist.
Power Ratings: Measured under SAE J1349 standards. Output is consistent across applications (Hyundai PT‑2019).
Hyundai Technical Information System (TIS): Docs ENG‑G4KJ‑001, ENG‑G4KJ‑002, TSB‑ENG‑112
VCA Type Approval Database (VCA/EMS/9215)
SAE International: J1349 Engine Power Certification Standards
The Hyundai G4KJ was used across Hyundai's PB/FD/HD/SU2 platforms with transverse mounting and no external licensing. This engine received platform-specific adaptations—revised engine mounts in the Venue SU2 and updated intake manifolds in the i30 HD—and from mid‑2017 the facelifted i20 PB adopted updated camshafts per TSB‑ENG‑112, creating minor interchange limits. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped on the front face of the cylinder block near the timing cover (Hyundai TIS ENG‑G4KJ‑005). The 7th VIN digit for G4KJ-equipped vehicles is typically 'K'. All units feature black cam covers; pre-06/2017 engines have smooth cam lobes with standard retainers, while post-06/2017 units feature hardened cam lobes and reinforced retainers per TSB‑ENG‑112. Critical differentiation from G4FG (1.4L): G4KJ has larger displacement (1,591 cc vs. 1,396 cc) and higher torque output. Service parts require verification—exhaust camshafts before 06/2017 are not interchangeable with later units due to lobe profile and material changes (Hyundai TSB‑ENG‑112).
The G4KJ's primary reliability risk is exhaust camshaft lobe wear on early builds (pre-06/2017), with elevated incidence in high-RPM or stop-start urban use. Hyundai internal quality data from 2018 indicated a measurable rate of cam wear in engines exceeding 100,000 km without strict oil maintenance, while UK DVSA MOT records show low failure rates overall due to robust emissions hardware. Extended oil intervals and infrequent warm-up cycles increase lobe stress, making oil quality and change frequency critical.
Analysis derived from Hyundai technical bulletins (2016–2021) and UK DVSA failure statistics (2018–2023). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about HYUNDAI G4KJ.
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