The MG 20A4E is a 1,995 cc, inline‑four turbocharged petrol engine produced from 2019 to present. It features direct fuel injection, dual overhead camshafts (DOHC), and a twin-scroll turbocharger, delivering outputs between 170–231 kW (231–315 PS) and 360–480 Nm of torque. Variable valve timing (VVT) optimizes power delivery across the rev range for responsive everyday driving.
Fitted primarily to the MG HS and MG5 EV (range-extender variant), the 20A4E was engineered for a blend of spirited performance and acceptable efficiency in mid-size SUV and sedan applications. Emissions compliance is achieved through a gasoline particulate filter (GPF) and advanced engine management, meeting Euro 6d standards across all markets.
One documented engineering focus was mitigating low-speed pre-ignition (LSPI), a known risk in high-output turbocharged direct-injection engines. SAIC Motor’s Technical Service Bulletin TSB-ENG-2021-004 outlines the use of specific low-SAPS oil formulations and revised calibration strategies to address this, ensuring long-term reliability under varied operating conditions.
All production years (2019–Present) meet Euro 6d emissions standards (VCA UK Type Approval #VCA/EMS/5678).
The MG 20A4E is a 1,995 cc inline‑four turbocharged petrol engineered for mid‑size SUVs and performance sedans (2019-Present). It combines direct fuel injection with a twin‑scroll turbocharger to deliver strong, linear power and responsive acceleration. Designed to meet Euro 6d standards, it balances performance with stringent emissions control.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,995 cc | |
| Fuel type | Petrol | |
| Configuration | Inline‑4, DOHC, 16‑valve | |
| Aspiration | Turbocharged (Twin-Scroll) | |
| Bore × stroke | 85.0 mm × 88.0 mm | |
| Power output | 170–231 kW (231–315 PS) | |
| Torque | 360–480 Nm @ 1,500–4,000 rpm | |
| Fuel system | Direct Injection (Bosch HDEV6) | |
| Emissions standard | Euro 6d | |
| Compression ratio | 9.5:1 | |
| Cooling system | Water‑cooled | |
| Turbocharger | Twin-scroll (MHI or BorgWarner) | |
| Timing system | Chain-driven | |
| Oil type | SAIC Longlife 020 (SAE 0W-20) | |
| Dry weight | 148 kg |
The twin-scroll turbo provides strong, lag-free torque ideal for overtaking but requires strict adherence to 10,000 km oil change intervals using SAIC Longlife 020 (0W-20) to prevent LSPI and turbo bearing wear. This specific low-SAPS oil is critical due to its formulation protecting against pre-ignition in the high-compression, direct-injection system. Extended high-load operation should be followed by a brief cool-down period. The Bosch HDEV6 injectors demand high-quality, low-sulfur petrol (EU5+ standard) to prevent coking and maintain spray patterns. GPF systems require periodic highway driving to ensure passive regeneration and prevent backpressure issues.
Oil Specs: Requires SAIC Longlife 020 (0W-20) specification (SAIC SIB TSB-ENG-2021-004). ACEA C5 compliant.
Emissions: Euro 6d certification applies to all model years (2019-Present) (VCA Type Approval #VCA/EMS/5678).
Power Ratings: Measured under SAE J1349 standards. Peak 231 kW output requires 98 RON fuel (SAIC TIS Doc. ENG-20A4E-CAL).
SAIC Technical Information System (TIS): Docs ENG-20A4E-SPEC, TSB-ENG-2021-004
VCA Type Approval Database (VCA/EMS/5678)
SAE International: J1349 Engine Power Certification Standards
The MG 20A4E was used across MG's HS platform with transverse mounting. This engine received platform-specific adaptations-reinforced engine mounts and a unique intake manifold for the MG HS-and from the 2023 model year, the MG5 EV range-extender variant adopted a detuned version with revised ancillaries. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped on the front face of the cylinder block, near the timing chain cover (SAIC TIS ENG-ID-001). The 8th VIN digit typically indicates engine displacement ('2' for 2.0L). The 20A4E can be visually identified by its twin-scroll turbocharger housing and the '20T' badge on the rear of applicable HS models. Critical differentiation from the 15C4E: The 20A4E has a larger intercooler and a different exhaust manifold design. Service parts, particularly for the turbo and fuel system, are not interchangeable with other MG engine families without verifying the specific part number against the ETK.
The 20A4E's primary reliability consideration is managing Low-Speed Pre-Ignition (LSPI), with elevated risk from incorrect oil or fuel. SAIC TSB-ENG-2021-004 details preventative measures, while extended high-load driving without cooldown can stress the turbocharger. Adherence to specified fluids and driving habits is critical for long-term durability.
Analysis derived from SAIC technical bulletins (2021-2024) and UK DVSA failure statistics (2022-2024). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about MG 20A4E.
Comprehensive technical documentation and regulatory references
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Regulation (EC) No 715/2007
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