4 Runner 4WD V6-180.5 2959cc 3.0L SOHC (3VZ-E) (1989)
Catalytic Converter: Description and Operation
The catalytic converter consists of an aluminum carrier coated with a catalyst (active material) such as platinum or palladium which is enclosed in a
heat resistant steel shell. The catalyst material uses residual oxygen in the exhaust gasses and secondary air from the AS systems to convert HC, CO, and
in some cases NOx, into less harmful substances. The three way catalyst (TWC) reduces oxides of nitrogen (NOx) as well as HC and CO, producing
nitrogen, water, and carbon dioxide.