The Toyota NZ engine family is a straight-4 piston engine series. The 1NZ series uses aluminum engine blocks and DOHC cylinder heads. It also uses sequential fuel injection, and has 4 valves per cylinder with VVT-i. The engines are produced by Toyota's Kamigo Plant in Toyota, Aichi, Japan (for Prius, Vitz, ist and Sienta); by Siam Toyota Manufacturing in Chonburi, Thailand (1NZ for Yaris and Vios); and by Indus Motor Company in Karachi, Pakistan (2NZ for Corolla).

1NZ-FXE

The 1NZ-FXE is a hybrid 1497 cc version. Bore and stroke is 75x84.7 mm. It features forged steel connecting rods and an aluminum intake manifold. The engine has a high physical compression ratio of 13.0:1, but the closing of the inlet valve is delayed, for an effective compression ratio of 9.5:1. The net result is that the engine has a greater effective expansion than compression—making it a simulated Atkinson cycle, rather than a conventional Otto cycle. The reduction in cylinder charge means reduced torque and power output, but efficiency is increased. This combination makes the 1NZ-FXE suitable for use with the Hybrid Synergy Drive, where peak torque and power demands can be met by the electric motor and battery. Output is 76 hp at 5000 rpm with 115 Nm of torque at 4000 rpm. Peak thermal efficiency is about 37%. Production was discontinued in 2009, with the arrival of the 3rd generation Prius, which replaced the 1NZ-FXE with the 2ZR-FXE. In 2012, upon the arrival of the Prius c (North America), the Aqua (Japan), and the Yaris Hybrid (Europe), an improved version was introduced. Without any belt-driven accessories, and a physical compression ratio of 13.4:1, the new version delivers an output of 74 hp at 4800 rpm with 111 Nm of torque at 3600–4400 rpm. The 1NZ-FXE Hybrid Synergy Drive in the Toyota Prius has won several International Engine of the Year awards: Applications:

1NZ-FXP

The 1NZ-FXP is a hybrid 1497 cc version. Bore and stroke is 75x84.7 mm. It features forged steel connecting rods and an aluminum intake manifold. The engine has a high physical compression ratio of 13.0:1, but the closing of the inlet valve is delayed, for an effective compression ratio of 9.5:1. The net result is that the engine has a greater effective expansion than compression—making it a simulated Atkinson cycle, rather than a conventional Otto cycle. The reduction in cylinder charge means reduced torque and power output, but efficiency is increased. This combination makes the 1NZ-FXP suitable for use with the Hybrid Synergy Drive, where peak torque and power demands can be met by the electric motor, battery and LPG-hybrid system. Output is 76 hp at 5000 rpm with 115 Nm of torque at 4000 rpm. Peak thermal efficiency is about 37%. Applications:

1NZ-FE

The 1NZ-FE is a 1497 cc conventional Otto-cycle variant of the 1NZ-FXE with VVT-i on the intake camshaft. The engine block is found in many Toyota models assembled in Japan and Asian countries. It retains the same bore and stroke, but the compression ratio is lowered to 10.5:1 (increased to 11.0:1 in 2012 for the Japanese market). Output is 103-110 PS at 6000 rpm with 132-143 Nm of torque at 4200–4800 rpm. The redline is 6400 rpm. A CNG version called 1NZ-FNE was produced from April 2003, exclusively for the first generation Toyota Probox (NCP52V) until its discontinuation in 2014. It has 12.0:1 compression ratio, output is 92 PS at 6000 rpm with 125 Nm of torque at 4000 rpm. Applications:

1NZ-FE Turbo

The 1NZ-FE Turbo is a 1497 cc with an air-to-air intercooler turbocharged conventional Otto-cycle variant of the 1NZ-FE with VVT-i developed by Toyota Racing Development (TRD). The engine block is found in many Toyota models assembled in Asian countries. It retains the same bore and stroke, even the same 10.5:1 compression ratio as the naturally aspirated sibling. Output is 141-150 hp at 6000 rpm with 196-206 Nm of torque at 4000–4800 rpm. The redline is 6400 rpm. In Japan, this unique engine was available through modified Toyota cars (tuned by TRD or Modellista (ja)) and sold officially as complete car at Toyota dealers. The turbocharger kits is also available for sale at selected Toyota dealers or TRD official store. Applications:

2NZ-FE

The 2NZ-FE is a 1298 cc version. Bore and stroke is 75x73.5 mm, with a compression ratio of 10.5:1. Output is 63-65 kW at 6000 rpm with 121-123 Nm of torque at 4400 rpm. In 2000, it won the International Engine of the Year award in the 1-litre to 1.4-litre category. Applications:

Great Wall Motors version

In 2008, Great Wall Motors (GWM) introduced 1.3 L and 1.5 L engines codenamed GW4G13 and GW4G15. Despite the similar codes, they have nothing to do with the Mitsubishi 4G1x engines, but instead derived from NZ design. For example, the NZ engines are using timing chain to connect the crankshaft and camshafts, while the Mitsubishi 4G1x engines are using the less durable timing belt. Visually, this engine looks similar like the NZ engines such as the pulleys position and mechanically also share similarities such as the same bore x stroke size, engine displacement and interchangeable parts. No statement from GWM or Toyota regarding the confirmation if these engines are officially licensed by GWM. But according the official press release by GWM in 2009, these GW4G1x engines were independently developed by themselves. The turbocharged variants of the 1.5 L engine called GW4G15T was introduced in 2011 and followed by the higher output GW4G15B in the following year. These engines were discontinued in 2019, replaced by the cleaner GW4G15F to comply with China's National V emission standard. Further new variants that comply with National VI emission standard codenamed GW4G15K, GW4G15M and the naturally aspirated hybrid GW4G15H are also produced.

GW4G13

Power: 68 kW at 6,000 rpm Torque: 118 Nm at 4,200 rpm Applications:

GW4G15

Power: 78 kW at 6,000 rpm Torque: 138 Nm at 4,200 rpm Applications:

GW4G15T

Power: 98 kW at 5,600 rpm Torque: 188 Nm at 2,000–4,500 rpm Applications:

GW4G15B

Power: 110 kW at 5,600 rpm Torque: 210 Nm at 2,200–4,500 rpm Applications:

GW4G15F

Power: 110 kW at 5,600–6,000 rpm Torque: 210 Nm at 1,800–4,400 rpm Applications:

GW4G15K

Power: 110 kW at 5,500–6,000 rpm Torque: 220 Nm at 2,000–4,400 rpm Applications:

GW4G15M

Power: 110 kW at 5,500–6,0000 rpm Torque: 218 Nm at 1,800–4,400 rpm Applications:

GW4G15H

Power: 70 kW (engine) 110 kW (electric motor) 139 kW (combined) Torque: 125 Nm (engine) 250 Nm (electric motor) 375 Nm (combined) Applications: