# Toyota AR engine
The Toyota AR engine is a family of inline-four piston gasoline engines produced by Toyota Motor Corporation since 2008, spanning displacements from 2.0 to 2.7 liters and serving as the four-cylinder powerplant for the Camry, RAV4, Highlander, Venza, Sienna, Scion tC, and several Lexus hybrids.[18](https://global.toyota/en/newsroom/toyota/22893603.html) Toyota's 75-year history records the AR series of in-line, 4-cylinder gasoline engines as developed in August 2008, with production for the RAV4 beginning at the Kamigo Plant in July 2008.[1](https://www.toyota-global.com/company/history_of_toyota/75years/data/automotive_business/products_technology/technology_development/engines/index.html) • [2](https://www.toyota-global.com/company/history_of_toyota/75years/data/automotive_business/production/production/japan/general_status/kamigo.html)
| Key fact | Detail |
|---|---|
| Family | Inline-4 gasoline engine series developed August 2008; displacements include 2.5-liter (2AR) and 2.7-liter (1AR) types[1](https://www.toyota-global.com/company/history_of_toyota/75years/data/automotive_business/products_technology/technology_development/engines/index.html) • [3](https://global.toyota/en/detail/209895) |
| 2AR-FE specifications | 2,494 cc, bore × stroke 90.0 × 98.0 mm, 16-valve DOHC, compression 10.4:1, 134 kW (180 hp) at 6,000 rpm, 235 N·m at 4,100 rpm[4](https://toyotaspace.com/wp-content/uploads/2024/11/2AR-FE.pdf) |
| Key technologies | Dual VVT-i variable valve timing, Direct Ignition System, Acoustic Control Induction System (ACIS), Electronic Throttle Control System-intelligent (ETCS-i)[4](https://toyotaspace.com/wp-content/uploads/2024/11/2AR-FE.pdf) |
| Variants | 1AR-FE, 2AR-FE, 2AR-FXE (Atkinson-cycle hybrid), 2AR-FSE (D-4S direct injection), 3AR-FE, 4AR-FXE, 5AR-FE, 6AR-FSE, 8AR-FTS[5](https://www.toyota-tech.eu/SST/2013/Introduction.pdf) |
| Production sites | Kamigo Plant (Japan, from July 2008); Toyota Industries (from December 2008); TMMK Kentucky and Toyota Motor Manufacturing Alabama[2](https://www.toyota-global.com/company/history_of_toyota/75years/data/automotive_business/production/production/japan/general_status/kamigo.html) • [6](https://www.toyota-industries.com/investors/items/p06e-p17_1.pdf) • [7](https://global.toyota/en/detail/152282) |
| Hybrid version | 2AR-FXE developed September 2011; in the Japan-market Camry Hybrid it produces 118 kW (160 PS) at 5,700 rpm and 213 N·m at 4,500 rpm with a 12.5:1 compression ratio[1](https://www.toyota-global.com/company/history_of_toyota/75years/data/automotive_business/products_technology/technology_development/engines/index.html) • [8](https://toyota.jp/ucar/catalog/brand-TOYOTA/car-CAMRY/201209/10078222/) |
| Known issue | Brief knock or rattle noise at cold startup on 2009-2013 vehicles with 1AR-FE and 2AR-FE engines, addressed by Toyota technical bulletin T-SB-0041-13[9](https://static.nhtsa.gov/odi/tsbs/2013/MC-10133786-9999.pdf) |
## Design and technology
The 2AR-FE, the family's most widely used member, is an in-line, 4-cylinder, 2.5-liter, 16-valve DOHC engine with chain-driven camshafts and a pentroof combustion chamber.[4](https://toyotaspace.com/wp-content/uploads/2024/11/2AR-FE.pdf) It uses the Dual VVT-i system, which varies valve timing on both the intake and exhaust camshafts, together with a direct ignition system, the Acoustic Control Induction System, and [electronic throttle control](https://www.edgepedia.org/electronic-throttle-control).[4](https://toyotaspace.com/wp-content/uploads/2024/11/2AR-FE.pdf) ACIS changes the length of the intake tract in two stages according to engine speed and throttle angle, broadening the torque range.[10](https://parts.olathetoyota.com/ar-series-engines)
Compared with the 2AZ-FE it replaced in the RAV4, the 2AR-FE grew from 2,362 cc to 2,494 cc, raised compression from 9.8:1 to 10.4:1, and increased SAE net output from 124 kW (166 hp) to 134 kW (180 hp) at 6,000 rpm, with torque up from 224 N·m to 235 N·m.[4](https://toyotaspace.com/wp-content/uploads/2024/11/2AR-FE.pdf) The engine's service mass, with oil and coolant filled, is 147 kg.[4](https://toyotaspace.com/wp-content/uploads/2024/11/2AR-FE.pdf) Secondary sources describe an all-aluminum block and head, an offset crankshaft, roller-rocker valvetrain, reduced-tension piston rings, and a three-stage variable oil pump as low-friction measures.[10](https://parts.olathetoyota.com/ar-series-engines) • [11](https://www.motorreviewer.com/engine.php?engine_id=77)
Toyota described the AR as an advanced engine bringing together its state-of-the-art technologies, with substantially improved fuel efficiency despite larger displacement, higher maximum output, cleaner emissions, and lower noise.[3](https://global.toyota/en/detail/209895)
## Variants and applications
The family opened with the 1AR-FE, a 2.7-liter engine introduced in 2008 for the Venza and Highlander, later fitted to the Sienna and [Lexus RX](https://www.edgepedia.org/lexus-rx).[10](https://parts.olathetoyota.com/ar-series-engines) The 2AR-FE followed as the 2.5-liter option for the RAV4, Camry from 2009, and the [Scion tC](https://www.edgepedia.org/scion-tc).[10](https://parts.olathetoyota.com/ar-series-engines) Later members listed in Toyota's service documentation include the 3AR-FE, 4AR-FXE, 5AR-FE, 6AR-FSE, and the turbocharged 8AR-FTS.[5](https://www.toyota-tech.eu/SST/2013/Introduction.pdf)
**Hybrid and direct-injection versions.** The 2AR-FXE runs the [Atkinson cycle](https://www.edgepedia.org/atkinson-cycle), in which intake-valve closing is delayed so the expansion ratio exceeds the compression ratio, for use with Toyota's hybrid systems; Toyota's timeline records its development in September 2011.[1](https://www.toyota-global.com/company/history_of_toyota/75years/data/automotive_business/products_technology/technology_development/engines/index.html) In the ninth-generation Japan-market Camry, released September 2011, all newly marketed models became hybrids using the THS II system with the 2.5-liter Atkinson-cycle 2AR-FXE, delivering 26.5 km/l in the 10-15 mode and 23.4 km/l in JC08 mode with a system output of 151 kW (205 PS).[12](https://www.toyota-global.com/company/history_of_toyota/75years/vehicle_lineage/car/id60017422/index.html) The engine itself is rated at 118 kW (160 PS) at 5,700 rpm and 213 N·m at 4,500 rpm, with 2,493 cc displacement and a 12.5:1 compression ratio.[8](https://toyota.jp/ucar/catalog/brand-TOYOTA/car-CAMRY/201209/10078222/) The 2AR-FSE adds the D-4S dual direct-and-port injection system; in the [Lexus RC](https://www.edgepedia.org/lexus-rc) 300h it produces 176 hp at 6,000 rpm and 163 lb-ft at 4,800 rpm, with total hybrid system output of 217 hp.[13](https://pressroom.lexus.com/lexus-unveils-rc-coupe-2013-tokyo-motor-show/) Lexus also fitted the 2AR-FXE to the NX 300h, tuned with a water-to-oil cooler for the electric drive motor and a revised front drive reduction ratio.[14](https://pressroom.lexus.com/lexus-2015-nx-200t-300h-product-news/)
## Production
Production of the AR engine for the RAV4 began at Toyota's Kamigo Plant in July 2008.[2](https://www.toyota-global.com/company/history_of_toyota/75years/data/automotive_business/production/production/japan/general_status/kamigo.html) Toyota Industries Corporation, the group's engine-manufacturing affiliate, began producing 2.5-liter AR gasoline engines in December 2008, initially for the RAV4 and later for the Camry; its AR production reached 134,000 units in fiscal 2010.[6](https://www.toyota-industries.com/investors/items/p06e-p17_1.pdf) In North America the engine is produced by Toyota Motor Manufacturing, Kentucky (TMMK) and Toyota Motor Manufacturing, Alabama, and is used in the Camry, RAV4, Sienna, Highlander, and Venza; TMMK's engine capacity was about 440,000 units per year as of 2012.[7](https://global.toyota/en/detail/152282) A joint-venture plant in China also began producing the engine in 2.5-liter, 2.7-liter, and hybrid versions.[3](https://global.toyota/en/detail/209895)
## Service history
Toyota issued technical service bulletin T-SB-0041-13 (March 15, 2013) for a brief knock or rattle noise from the engine compartment lasting approximately one second immediately after a cold-soak startup on 2009-2013 model year vehicles equipped with the 1AR-FE and 2AR-FE engines; the repair procedure centers on the intake-side VVT gear and timing chain components.[9](https://static.nhtsa.gov/odi/tsbs/2013/MC-10133786-9999.pdf) The predecessor 2AZ-FE, by contrast, was subject to a Warranty Enhancement Program (ZE7) covering piston ring or piston replacement for excessive oil consumption on certain 2007-2015 model year Corolla, Matrix, Camry, Camry Hybrid, Scion tC, and RAV4 vehicles; secondary sources note the 2AR's revised piston and ring design addressed that pattern.[15](https://static.nhtsa.gov/odi/tsbs/2015/MC-10111318-9999.pdf) • [16](https://cargeek.org/engines/toyota-2ar)
## Succession
In December 2016 Toyota introduced the A25A-FKS, the 2.5-liter member of its new Dynamic Force engine line built on TNGA, as the successor to the 2AR-FE. The new engine achieves a maximum thermal efficiency of 40 percent in gasoline vehicles and 41 percent in hybrid vehicles, with 2,487 cc displacement, a 13:1 compression ratio (14:1 in the hybrid version), and D-4S injection.[17](https://global.toyota/en/powertrain/engine)
## References
1. [75 Years of TOYOTA: Technical Development, Engines, Toyota Motor Corporation](https://www.toyota-global.com/company/history_of_toyota/75years/data/automotive_business/products_technology/technology_development/engines/index.html)
2. [75 Years of TOYOTA: General Status of Plants in Japan, Kamigo Plant](https://www.toyota-global.com/company/history_of_toyota/75years/data/automotive_business/production/production/japan/general_status/kamigo.html)
3. [Toyota Joint-venture Engine Plant in China Begins Production of New Four-Cylinder Engine, Toyota Global Newsroom](https://global.toyota/en/detail/209895)
4. [RAV4 New Features: 2AR-FE Engine (Toyota training document)](https://toyotaspace.com/wp-content/uploads/2024/11/2AR-FE.pdf)
5. [Toyota Special Service Tools Introduction (AR series engine list)](https://www.toyota-tech.eu/SST/2013/Introduction.pdf)
6. [Toyota Industries Report 2010: Enhancing Our Development Capabilities](https://www.toyota-industries.com/investors/items/p06e-p17_1.pdf)
7. [Toyota to Up Engine Production Capacity at Kentucky Plant in U.S., Toyota Global Newsroom](https://global.toyota/en/detail/152282)
8. [Toyota Certified Used Cars: Camry Hybrid (2012) specifications, Toyota Japan](https://toyota.jp/ucar/catalog/brand-TOYOTA/car-CAMRY/201209/10078222/)
9. [Toyota T-SB-0041-13: Brief Engine Knock/Rattle Noise at Cold Startup (1AR/2AR), NHTSA](https://static.nhtsa.gov/odi/tsbs/2013/MC-10133786-9999.pdf)
10. [Information About The Toyota AR Series Engine, Toyota Parts Center (Olathe)](https://parts.olathetoyota.com/ar-series-engines)
11. [Toyota 2AR-FE 2.5L Engine Specs, Problems, Reliability, MotorReviewer](https://www.motorreviewer.com/engine.php?engine_id=77)
12. [75 Years of TOYOTA: Vehicle Lineage, 9th-generation Camry](https://www.toyota-global.com/company/history_of_toyota/75years/vehicle_lineage/car/id60017422/index.html)
13. [Lexus Unveils All-New RC Coupe, Lexus USA Newsroom](https://pressroom.lexus.com/lexus-unveils-rc-coupe-2013-tokyo-motor-show/)
14. [All-New Lexus NX Compact Luxury-Utility, Lexus USA Newsroom](https://pressroom.lexus.com/lexus-2015-nx-200t-300h-product-news/)
15. [Toyota Service Consultant Reference Guide, Warranty Enhancement Program ZE7, NHTSA](https://static.nhtsa.gov/odi/tsbs/2015/MC-10111318-9999.pdf)
16. [Toyota 2AR engine: specifications, cars fitted and common faults, CarGeek](https://cargeek.org/engines/toyota-2ar)
17. [New 2.5-liter Direct-injection, Inline 4-cylinder Gasoline Engine (Dynamic Force), Toyota Global Newsroom](https://global.toyota/en/powertrain/engine)
18. [Toyota Gives the Crown a New Shine at Sixty, Toyota, Global Newsroom, Toyota Motor Corporation Official Global Website](https://global.toyota/en/newsroom/toyota/22893603.html)
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*Topic: Encyclopedia › Technology and the built world › Transport and spaceflight › Road transport › Automobiles › Automobile engines › Japanese engines*
*Initially written Sep 17, 2026 · Reviewed: Oct 15, 2026 · Edited: Oct 15, 2026; Oct 25, 2026 · Last review: Oct 15, 2026*
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