Toyota AZ engine. The Toyota AZ engine family is a straight-4 piston engine series. The AZ series uses an aluminium engine block with cast iron cylinder liners and aluminium DOHC cylinder head. The engine series features many advanced technologies including slant-squish combustion chambers, offset cylinder and crank centers, and the VVT-i continuously variable intake valve timing system. The aluminium engine measures  long,  wide, and  tall.

The cylinder block is an open-deck, midi-skirt die-cast aluminium type with cast-in iron liners and a die-cast aluminium lower crankcase and a stamped oil pan. The forged steel crankshaft is fully balanced with eight counterweights and supported by five main bearings. A helical gear pressed in No. 3 counterweight drives twin contra-rotating balance shafts in the shaft housing within the lower crankcase.

The dual overhead camshafts are driven by a single-stage roller chain of  pitch, enabling a narrow included valve angle of 27.5°. The camshafts act on four valves per cylinder via bucket tappets. As in the recent Toyota engine practice, no clearance adjusting shim is employed. Valve diameters are  for intake and  for exhaust, with  lift for both intake and exhaust. The four-vane VVT-i device is fitted on the intake camshaft, altering timing by 50°. The valve cover is made of magnesium to save weight.

Fuel is injected sequentially via an ultra-fine-atomization injector with twelve small injection holes, each  in diameter. As in the smaller NZ engine, the new AZ adopts a plastic, built-up, and vibration-welded intake manifold integrating a large volume plenum chamber ( volume including a  resonator). Exhaust manifolds are of tubular construction with integrated catalytic converters.

The AZ is the replacement for the S engine. Its successor is the AR engine.

Excessive oil consumption
The 2AZ-FE engine in the 2007-2009 Camry and 2006-2009 Rav4 may burn excessive oil and is involved in this lawsuit.  Other engines are also affected. If this Toyota engine is burning more than  of oil in , has less than , is less than 10 years old, and is located in the U.S., Toyota service will perform a free oil consumption test to determine if the engine is affected. There are approximately 1,715,200 vehicles covered by this Warranty Enhancement Program.

A similar campaign are also done in Japan by Toyota in 2014.

1AZ
The 1AZ line of engines have  of displacement.

1AZ-FE
The 1AZ-FE is a  version. Output is  at 6000 rpm with  of torque at 4000 rpm for the Camry Aurion version. Rav4 and Ipsum engines were rated at  at 6000 rpm and  of torque at 4000 rpm.

The 1AZ has a total displacement of  with  bore and stroke, and a compression ratio of 9.6:1.

 2002-2006 Toyota Camry (Southeast Asian/Taiwanese version)
 2006–2009 Toyota Camry (Aurion version)
 2000–2003 Toyota RAV4
 2003-2006 Toyota RAV4 Euro
 2001–2009 Toyota Ipsum
 2004–2008 Toyota Wish (Southeast Asian/Taiwanese version)

1AZ-FSE
The 1AZ-FSE is a  version.  Bore and stroke is , and a compression ratio of 11.0:1. Output is  at 5700 rpm with  of torque at 4000 rpm. The 1AZ-FSE features Toyota's D-4 direct injection system.

 2000-2003 Toyota Avensis T220 (Facelift)
 2003-2008 Toyota Avensis T250
 Toyota Avensis Verso
 Toyota Noah/Voxy
 Toyota RAV4
 Toyota Gaia
 Toyota Isis
 Toyota Ipsum
 Toyota Caldina
 Toyota Wish
 Toyota Nadia
 Toyota Allion
 Toyota Premio
 Toyota Opa

2AZ
The 2AZ line of engines have  of displacement.

2AZ-FE
The 2AZ-FE is a  version built in Japan (Kamigo Plant and by Toyota Industries Corporation), at TMMK in the USA and also built in China for select Scion xB models, and also in Australia, obtains a total displacement of  with  bore and stroke, with a compression ratio of 9.6:1. Output is  at 5600 rpm;  of torque at 4000 rpm.

Later versions of the 2AZ-FE engine were upgraded with 9.8:1 compression ratio, a slightly more aggressive intake cam profile, 6500 rpm redline, and piston oil squirters. These later versions are rated at  in the Scion tC,  in the RAV4, and  in the Camry, Corolla XRS, Scion xB, and   for the Previa/Estima/Alphard.

Japan-made Toyota vehicles with the 2AZ-FE engine were equipped with the K112 transmission also referred to as 7-speed Super CVT-i automatic (Seven-speed Sequential Shiftmatic) from October 2005.

However, these later 2AZ-FE models were the first to be rated under the new SAE J1349 standard. The new standard usually produces more conservative numbers, though no definitive comparison is available since the two versions were never tested by the same standard. The RAV4 uses a different timing chain cover from the Camry, they can however be interchanged.

A TRD supercharger was available for the Scion tC and 2nd generation xB until Spring 2009.

There have been complaints of this engine "burning oil" in North America, with the issue starting after , though mostly after . Piston ring design has been identified as a potential problem. Toyota has issued a TSB (Technical service bulletin) TSB #0094-11 in August 2011 but has not issued a recall. Alternative theories point to a head gasket problem: the 2AZ-FE aluminum block threads may wear out on the back three middle bolts (closest to firewall). Check TSB SB-0015-11.

There are several class-action lawsuits underway regarding this issue. In January 2015, Toyota North America issued extended warranty notification (ZE7) for this issue for Toyota North America vehicles only.

 2002–2011 Toyota Camry in Australia. ACV40R
 2009–2011 Toyota Matrix S (USA)/XR (Canada)/XRS
 2009–2010 Pontiac Vibe
 2009–2010 Toyota Corolla XRS (2011-2013 only in Mexico and in Canada)
 2002–2008 Toyota Camry Solara
 2004–2012 Toyota RAV4
 2000–2007 Toyota Highlander/Kluger
 2000−2013 Toyota Harrier
 2000-2019 Toyota Estima /  Toyota Previa / Toyota Tarago
 2001-2010 Toyota Ipsum
 2002−2015 Toyota Alphard
 2008−2015 Toyota Vellfire
 2006−2012 Toyota Blade
 2003-2009 Toyota Avensis
 2005–2010 Scion tC
 2008–2015 Scion xB
 2007-2013 Toyota Mark X ZiO

2AZ-FSE
The 2AZ-FSE is a  version. Bore and stroke is , and a compression ratio of 11.0:1. Output is  at 5800 rpm with  of torque at 3800 rpm. The 2AZ-FSE features Toyota's D-4 direct injection system.

 Toyota Avensis

2AZ-FXE
The 2AZ-FXE is an Atkinson cycle variant of the 2AZ-FE. It has the same bore and stroke, but the intake cam and pistons are unique. It has a physical compression ratio of 12.5:1.

The longer than normal open intake valve duration leads to a reduction in cylinder charge and reduced torque and power output, but efficiency is increased. This combination makes the 2AZ-FXE suitable for use only in hybrid vehicles, where peak torque and power demands can be met by the electric motor and battery.

Maximum output when used in the Camry hybrid is  at 6000 rpm with  of torque at 4400 rpm.

 2003–2014 Toyota Alphard Hybrid
 Toyota Estima Hybrid
 2007–2011 Toyota Camry Hybrid AHV40
 2010–2014 Lexus HS 250h
 2009–2017 Toyota Sai

3AZ 
The 3AZ line of engines have  of displacement.

3AZ-FXE 
The 3AZ-FXE is an Atkinson cycle engine which is always paired to an electric motor in a hybrid system. This engine is an analogue of the 2AZ-FXE which is for the Chinese market only.

* 2010 Toyota Camry Hybrid AHV40 (China)

See also

 List of Toyota engines

References

AZ
Straight-four engines
Gasoline engines by model