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. 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