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 heads. 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. 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 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, and is less than 10 years old, Toyota service will perform a free oil consumption test to determine if your engine is affected. There are approximately 1,715,200 vehicles covered by this Warranty Enhancement Program.

1AZ

The 1AZ line of engines have displacements.

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.
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.
The 2AZ line of engines have displacements.

2AZ-FE

The 2AZ-FE is a version built in Japan, at TMMK in the USA and also built in China for select Scion xB models, 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. 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 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 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. 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 for this issue for Toyota North America vehicles only.
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.
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 large valve overlap 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.