Over the time the exhaust gas recirculation (EGR) system may become plugged with debris, the oxygen sensor may also be getting slow or 'lazy' around this time. When servicing or cleaning the EGR system, it is a good idea to replace the oxygen sensor because it works in tandem with the EGR system.Google+
Car Problem Reports
Toyota Land Cruiser Replace Oxygen Sensor When Servicing EGR System
Toyota Land Cruiser Problem
Average Mileage: 159,717 mi (102,153 mi - 250,000 mi)
Visitor, 1997 Toyota Land Cruiser, 127,000 mi
had to replace both oxygen sensors after check engine light was tripped. bought replacements on Amazon for 1/2 the price of lcoal store and replaced them myself in about an hour.
Visitor, 1991 Toyota Land Cruiser, 102,153 mi
High Nox, engine light.
Visitor, 1994 Toyota Land Cruiser
Diagnostic report: 02s2 malfunction. EGR system malfunction. Estimated cost $528.25 We are looking for a better price.