Hyundai Theta engine
|Manufacturer||Hyundai Motor Company|
2.0L (1998 cc) |
2.4L (2359 cc)
86 mm (2.0L) |
88 mm (2.4L)
86 mm (2.0L) |
97 mm (2.4L)
|Cylinder block alloy||Aluminium|
|Cylinder head alloy||Aluminium|
10.5:1 (2.0 L)|
10.3:1 (2.4 L)
|Management||EMS-II from Siemens VDO|
|Fuel type||Unleaded gasoline|
|Oil system||Pressure feed|
107 kW (143.4 hp) @ 6000 rpm (2.0 L) |
121 kW (162.2 hp) @ 5800 rpm (2.4L)
190 Nm (140.1 ft. ibs) @ 4000 rpm (2.0 L) |
222 Nm (163.7 ft. ibs) @ 4250 rpm (2.4L)
|Dry weight||134 kg (2.0L)|
The Hyundai Theta (G4KC) is a gasoline four-cylinder automobile engine family. The third all-aluminum engine of Hyundai Motor Company debuted in the fourth-generation Hyundai Sonata sedan (codenamed NF), which was unveiled in August 2004 in South Korea. Hyundai Motor Manufacturing Alabama (HMMA) built a Theta II engine shop on the grounds of their Montgomery, Alabama automobile factory.
Global Engine Alliance
The Global Engine Alliance was a joint venture between Chrysler, Mitsubishi Motors, and the Hyundai Motor Company for developing a line of shared 4-cylinder engines. The initial design of the engine block and cylinder head was handled by Hyundai. However, each manufacturer configured their variants of the initial design differently based on their needs. In 2009, Chrysler bought out Mitsubishi and Hyundai's stake in the joint-venture; however, each company retained rights to build the engines.
The first version of the Theta Engine had two variants, the 2.0L and the 2.4L.
2.0L - G4KA
The 2.0L version is an inline 4-cylinder engine that carries a bore and stroke of 86 mm and a 10.5:1 compression ratio; the engine makes 143 hp (107 kW; 145 PS) at 6,000 rpm and 140 lb⋅ft (190 N⋅m) of torque at 4,000 rpm. It uses a timing chain instead of belt, and the engine dry weight is 134 kg (295 lb).
2.4L - G4KC
The 2.4L version is an inline 4-cylinder engine that carries a bore of 88.0 mm, stroke of 97.0 mm and a 10.3:1 compression ratio; the engine makes 162 hp (121 kW; 164 PS) at 5,800 rpm and 164 lb⋅ft (222 N⋅m) of torque at 4,250 rpm.
2.0L - G4KD
The engine features hollow stainless-steel dual overhead camshafts (DOHC) with powder-metal cam lobes, pent-roof combustion chambers and shimless bucket tappets in the cylinder head. BorgWarner Morse TEC supplies the complete timing system which uses the company's proprietary silent timing chains. Continuously variable valve timing (CVVT) works on the intake side.
The aluminum alloy engine block, which is formed using a high-pressure die-cast method, has a unique Metaldyne-supplied cassette-type balance shaft module with a two-stage oil pump built-in. In the lower-end, the block is reinforced by a ladder frame. Other notable features include fracture-split sinter-forged connecting rods manufactured by Sinteron and a stainless-steel exhaust manifold.
Theta's EMS (engine management system) software is EMS-II from Siemens VDO and the 32-bit PCM (Powertrain Control Module) calculates the amount of intake air by utilizing a contamination-proof hot-film type MAF (mass air flow) sensor.
The MPI version of the 2.0L Theta engine has a 10.5:1 compression ratio, and it produces 163 hp (122 kW; 165 PS) at 6,200 rpm and 146 lb⋅ft (198 N⋅m) of torque at 4,600 rpm and is available in the Middle East.
The MPI version of the 2.4L Theta engine has a 10.3:1 compression ratio, and it produces 176 hp (131 kW; 178 PS) at 6,000 rpm and 168 lb⋅ft (228 N⋅m) of torque at 4,000 rpm and is available in the Middle East and Europe.
Theta/Theta-II Engine - 2.0L (1998cc)
(G4KA, G4KD, G4KF, G4KH, G4KL)
- Genesis G70 GDI 2.0 Turbocharged (2019-)
- Hyundai Genesis Coupe Port Injected 2.0 Turbocharged (2010-2014)
- Hyundai i30 N TCR GDI 2.0 Turbocharged
- Hyundai ix35 MPI 2.0 (2010-)
- Hyundai Santa Fe (Sport Models) GDI 2.0 Turbocharged (2013-)
- Hyundai Sonata GDI 2.0 Turbocharged (2011-)
- Kia Forte 2.0 (2009-2013)
- Kia Optima GDI 2.0 Turbocharged (2011-)
- Kia Rondo (2007-)
- Kia Sorento GDI 2.0 Turbocharged (2016-)
- Kia Sportage GDI 2.0 Turbocharged (2011-)
- Kia Stinger GDI 2.0 Turbocharged (2018-)
Theta/Theta-II Engine - 2.4L (2359cc)
(G4KC, G4KE, G4KG, G4KJ,)
- Hyundai Sonata (2006–2010)
- Hyundai Sonata GDI (2011-)
- Hyundai Sonata (2011-) (Middle East)
- Hyundai Tucson (2010-)
- Hyundai Santa Fe (2010-)
- Hyundai Starex (2007-)
- Kia Optima (2006–2010)
- Kia Optima GDI (2011-)
- Kia Rondo (2007-)
- Kia Cadenza GDI (2011-)
- Kia Sportage (2011-)
- Kia Sorento (2011-)
- Kia Forte (2010-2013)
2.0T GDI turbo
In the 2009-2012 Genesis coupe turbo, it produced 210 hp (213 PS) @ 6,000 rpm on 87 octane (AKI) gasoline, and 223 hp (226 PS) on 93 AKI. Torque remains the same at 223 lb⋅ft (302 N⋅m) @ 2000 rpm. In the 2013-2014 model,the engines got upgraded, the new 2.0T now produces 274 hp (204 kW; 278 PS) and 275 lb·ft (373 N·m) torque due to a bigger turbo The Theta block used is very similar to the Mitsubishi Evolution X 4B11T, as core components like pistons and rods are said should move freely between them, however, the two engines are not identical. The 4B11T is a semi-closed deck block with larger oil and coolant passages, where as the Theta is an open deck block.
The 2.0L GDI turbo in (2011-2014 Sonata) develops 274 hp (278 PS) and 269 lb⋅ft (365 N⋅m) of torque. The fuel economy is rated at 22mpg (10.7L / 100KM) in the city and 34mpg (6.92L / 100KM) on the highway. It comes exclusively with a 6-speed automatic transmission.
The 2.0L GDI turbo in 2019 Hyundai Veloster N and i30 N develops 271 hp (275 PS) and 260 lb⋅ft (353 N⋅m) of torque. The fuel economy is rated at mpg (L / 100KM) in the city and mpg (L / KM) on the highway. It comes exclusively with a 6-speed manual transmission.
The 2.0L GDI turbo in 2019 Genesis G70 develops 255 hp (259 PS) and 260 lb⋅ft (353 N⋅m) of torque. The fuel economy is rated at mpg (L / 100KM) in the city and mpg (L / KM) on the highway. It comes with a 6-speed manual transmission in Sport model trim.
Hyundai and Kia vehicles equipped with Theta II engines and recalled because of those engines are the focus of an investigation by the National Highway Traffic Safety Administration (NHTSA). Safety regulators want to know if Hyundai and Kia did enough and fast enough concerning the recalls of nearly 1.7 million vehicles with Theta engines prone to a lot of noise and finally locking up.
In September 2015, Hyundai recalled about 470,000 model year 2011-2012 Sonatas equipped with 2-liter and 2.4-liter Theta II engines. At the time, Hyundai told NHTSA that manufacturing problems left metallic debris around the engine crankshaft, causing problems with oil flow. The pieces of metal interfere with the oil flow through the connecting rod bearings and damage the connecting rods. The automaker blamed the problem on a mechanical "deburring" process used to remove metallic machining debris from the crankshaft.
By April 2017, Hyundai expanded the 2015 recall by including another 572,000 vehicles with Theta II engines, including 2013-2014 Hyundai Sonata and Santa Fe Sport vehicles. Hyundai told safety regulators the same metal debris problem caused the expanded recall. Near that same time, Kia told NHTSA about a recall of more than 618,000 model year 2011-2014 Kia Optima, 2012-2014 Sorento and 2011-2013 Sportage vehicles because the Theta engine bearings wore out too early and caused the engines to seize. Kia said it didn't recall the vehicles in 2015 when Hyundai first recalled its cars because the Theta II engines in the Kia vehicles were built on a different production line and had different problems than Hyundai. In addition to customers complaining about the Theta II engines, a Korean whistleblower who worked for Hyundai as an engineer let NHTSA know what he knew.
Owners started suing after the automaker refused to pay the thousands of dollars to repair or replace the engines, with one lawsuit from 2015 alleging a dealer wanted $4,500 to do the work. Kia was also served papers over a class-action lawsuit in 2016 filed by owners of vehicles equipped with Theta engines. NHTSA says it took action to "investigate both the timeliness and scope of Hyundai's Theta II engine recalls, and Hyundai's compliance with reporting requirements."
On 2013-11-05, Hyundai announced the creation of a new factory crate engine program at the 2013 SEMA Show in Las Vegas, which initially included a 2.0-liter, turbocharged four-cylinder engine. The crate engine program began in December 2013.
- Chrysler World engine - Chrysler's GEMA built engines
- Mitsubishi 4B1 engine - Mitsubishi's GEMA built engines
- List of Hyundai engines
- Aaron Robinson. "2010 Hyundai Genesis Coupe 2.0T Turbo". Car and Driver (May 2009).
- "Hyundai and Kia Theta II Engine Recalls Investigated". CarComplaints.com. Retrieved 2018-07-17.
- Hyundai launches crate engine program with 2.0L four and 3.8L V6