The Kia Optima IV facelift, specifically the 2.0 GDI (205 Hp) Plug-in Hybrid Automatic variant, represents a significant step in Kia’s commitment to fuel efficiency and electrified powertrains. Produced from 2018 to 2020, this model year marked a mid-cycle refresh for the fourth-generation Optima (known as the K5 in more recent iterations), introducing updated styling and enhanced technology. The plug-in hybrid version was positioned as a premium offering within the Optima lineup, targeting environmentally conscious buyers seeking a balance between fuel economy and driving performance. It utilized the 1HX0 platform, shared with other Hyundai-Kia models, and was primarily sold in markets where plug-in hybrid incentives were available, including North America and Europe.
Technical Specifications
| Brand | Kia |
| Model | Optima |
| Generation | Optima IV (facelift 2018) |
| Type (Engine) | 2.0 GDI (205 Hp) Plug-in Hybrid Automatic |
| Start of production | 2018 |
| End of production | 2020 |
| Powertrain Architecture | PHEV (Plug-in Hybrid Electric Vehicle) |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (economy) – combined (NEDC) | 1.6 l/100 km (147 US mpg, 176.6 UK mpg, 62.5 km/l) |
| CO2 emissions (NEDC) | 37 g/km |
| Fuel Type | Petrol / electricity |
| Acceleration 0 – 100 km/h | 9.4 sec |
| Acceleration 0 – 62 mph | 9.4 sec |
| Acceleration 0 – 60 mph | 8.9 sec |
| Maximum speed | 192 km/h (119.3 mph) |
| Emission standard | Euro 6d-TEMP |
| Weight-to-power ratio | 8.3 kg/Hp, 120.2 Hp/tonne |
| Weight-to-torque ratio | 4.5 kg/Nm, 219.9 Nm/tonne |
| Gross battery capacity | 9.8 kWh |
| Net (usable) battery capacity | 7.8 kWh |
| Battery voltage | 360 V |
| Battery technology | Lithium-polymer (LiPo) |
| Battery weight | 131 kg (288.81 lbs.) |
| Battery location | Under the trunk |
| All-electric range (NEDC) | 54 km (33.55 mi) |
| Average Energy consumption (NEDC) | 12.2 kWh/100 km (19.63 kWh/100 mi, 172 MPGe, 8.2 km/kWh, 5.1 mi/kWh) |
| Max speed (electric) | 120 km/h (74.56 mph) |
| Electric motor power | 68 Hp @ 2330-3300 rpm |
| Electric motor Torque | 205 Nm @ 0-2330 rpm (151.2 lb.-ft. @ 0-2330 rpm) |
| Electric motor location | Between the combustion engine and the transmission |
| System power | 205 Hp @ 6000 rpm |
| System torque | 375 Nm @ 2330 rpm (276.59 lb.-ft. @ 2330 rpm) |
| Power | 154 Hp @ 6000 rpm |
| Power per litre | 77 Hp/l |
| Torque | 187 Nm @ 5000 rpm (137.92 lb.-ft. @ 5000 rpm) |
| Engine layout | Front, Transverse |
| Engine Model/Code | G4NG |
| Engine displacement | 1999 cm3 (121.99 cu. in.) |
| Number of cylinders | 4 |
| Engine configuration | Inline |
| Cylinder Bore | 81 mm (3.19 in.) |
| Piston Stroke | 97 mm (3.82 in.) |
| Compression ratio | 13.5:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Direct injection |
| Engine aspiration | Naturally aspirated engine |
| Valvetrain | DOHC, Dual CVVT |
| Engine oil capacity | 4.1 l (4.33 US qt | 3.61 UK qt) |
| Coolant | 6.7 l (7.08 US qt | 5.9 UK qt) |
| Kerb Weight | 1705-1775 kg (3758.88 – 3913.21 lbs.) |
| Max. weight | 2200 kg (4850.17 lbs.) |
| Max load | 425-495 kg (936.96 – 1091.29 lbs.) |
| Trunk (boot) space – minimum | 307 l (10.84 cu. ft.) |
| Fuel tank capacity | 55 l (14.53 US gal | 12.1 UK gal) |
| Length | 4855 mm (191.14 in.) |
| Width | 1860 mm (73.23 in.) |
| Width including mirrors | 2120 mm (83.46 in.) |
| Height | 1465 mm (57.68 in.) |
| Wheelbase | 2805 mm (110.43 in.) |
| Front track | 1602 mm (63.07 in.) |
| Rear (Back) track | 1609 mm (63.35 in.) |
| Front overhang | 965 mm (37.99 in.) |
| Rear overhang | 1085 mm (42.72 in.) |
| Ride height (ground clearance) | 135 mm (5.31 in.) |
| Drag coefficient (Cd) | 0.25 |
| Minimum turning circle (turning diameter) | 10.9 m (35.76 ft.) |
| Drivetrain Architecture | The Internal combustion engine (ICE) and electric motor drive the front wheels of the car with the ability to work in full electric or mixed mode. |
| Drive wheel | Front wheel drive |
| Number of gears and type of gearbox | 6 gears, automatic transmission |
| Front suspension | Independent, type McPherson with coil spring and anti-roll bar |
| Rear suspension | Independent multi-link spring suspension with stabilizer |
| Front brakes | Ventilated discs, 300 mm |
| Rear brakes | Disc, 300 mm |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Electric Steering |
| Tires size | 215/55 R17 |
| Wheel rims size | 7J x 17 |
INTRODUCTION
The 2018-2020 Kia Optima Plug-in Hybrid, powered by a 2.0-liter GDI engine paired with an electric motor and a 9.8 kWh battery pack, was a key component of Kia’s strategy to offer more environmentally friendly vehicles. This variant built upon the already well-received fourth-generation Optima, known for its stylish design and spacious interior. The plug-in hybrid system allowed for a significant amount of all-electric range – up to 54 km (33.55 miles) on the NEDC cycle – making it suitable for daily commutes and shorter trips. Positioned above the standard gasoline-powered Optima models, it competed with other plug-in hybrid sedans like the Toyota Prius Prime and Hyundai Sonata Plug-in Hybrid.
Powertrain & Engine Architecture
At the heart of the Optima Plug-in Hybrid is the G4NG 2.0-liter inline-four cylinder gasoline engine. This engine utilizes direct injection (GDI) technology and a dual continuously variable valve timing (DOHC, Dual CVVT) system to optimize efficiency and power output. The engine produces 154 horsepower and 137.92 lb-ft of torque. Coupled with the 68 hp electric motor, the combined system output reaches 205 horsepower and 276.59 lb-ft of torque. The electric motor is integrated between the engine and the six-speed automatic transmission, allowing for seamless transitions between electric, hybrid, and gasoline power. The lithium-polymer battery pack, with a usable capacity of 7.8 kWh, is located under the trunk floor, slightly reducing cargo space. The charging port is conveniently located on the driver’s side front fender.
Driving Characteristics
The Optima Plug-in Hybrid delivers a refined and comfortable driving experience. In all-electric mode, the vehicle offers near-silent operation and brisk acceleration for city driving. The electric motor provides instant torque, making it responsive in stop-and-go traffic. When the battery is depleted or requires assistance during acceleration, the gasoline engine seamlessly kicks in. The six-speed automatic transmission provides smooth gear changes, although it isn’t as quick-shifting as some dual-clutch transmissions found in competitors. Compared to the standard 1.6L Turbo Optima, the plug-in hybrid offers similar overall performance, but with the added benefit of electric-only driving. Compared to higher-horsepower gasoline versions, the plug-in hybrid prioritizes efficiency over outright speed, but the combined power output still provides adequate performance for most driving situations.
Equipment & Trim Levels
The Optima Plug-in Hybrid was typically offered in a single, well-equipped trim level. Standard features included leather upholstery, a touchscreen infotainment system with Apple CarPlay and Android Auto compatibility, a rearview camera, automatic climate control, and a suite of advanced safety features such as forward collision warning, lane departure warning, and automatic emergency braking. Optional extras often included a premium sound system, a panoramic sunroof, and adaptive cruise control. The interior design was similar to other Optima models, with a focus on comfort and user-friendliness.
Chassis & Braking
The Optima Plug-in Hybrid utilizes a McPherson strut front suspension and a multi-link rear suspension, providing a comfortable ride and predictable handling. The suspension is tuned to balance ride quality with handling performance, making it suitable for both city and highway driving. Braking duties are handled by ventilated discs at the front and solid discs at the rear. The vehicle is equipped with an anti-lock braking system (ABS) and electronic stability control (ESC) as standard safety features. Due to the added weight of the battery pack, the suspension components were slightly reinforced compared to the standard Optima models.
Market Reception & Comparison
The Kia Optima Plug-in Hybrid was generally well-received by automotive critics. Reviewers praised its fuel efficiency, comfortable ride, and spacious interior. The all-electric range was considered competitive within its segment. However, some critics noted that the trunk space was slightly reduced due to the battery pack. Compared to the standard Optima models, the plug-in hybrid offered significantly better fuel economy, but at a higher initial purchase price. Compared to other plug-in hybrid sedans, the Optima offered a compelling value proposition with its generous standard features and competitive pricing.
Legacy
The Kia Optima Plug-in Hybrid represented a significant step forward for Kia in the realm of electrified vehicles. While production ended in 2020, the model has proven to be relatively reliable, with few widespread issues reported. On the used car market, these models continue to be sought after by buyers looking for a fuel-efficient and environmentally friendly vehicle. The powertrain, while not without its complexities, has demonstrated reasonable long-term durability. The Optima Plug-in Hybrid paved the way for Kia’s continued expansion into the electric vehicle market, culminating in models like the Niro EV and EV6.
