Possible Faulty Oxygen Sensor Cause

[RichyR32GTR]

Found this in an article somewhere which interested me. I though i'd share it.

In most oxygen sensors there is a zirconia element that, when heated to temperatures above approximately 300 degC, produces voltages that are based on the oxygen content surrounding the sensor tip as compared to the oxygen in the atmosphere. Oxygen sensors perform this comparison through an atmospheric reference orifice in the sensor housing which, depending where the oxygen sensor is located on the exhaust system, is on the outside of the exhaust manifold, engine pipe or catalytic converter. If the atmospheric reference orifice is blocked with road grime, mud or in some cases, dried crankcase oil, the performance of the sensor will be impaired to a point that will result in poor fuel economy, excessive exhaust emissions and in severe cases vehicle drivability problems. Always visually inspect the oxygen sensor. If it is externally covered with any form of contaminant there is a very good likelihood that the sensor will not perform to optimum capacity due to the atmospheric reference orifice being blocked. Pay particular attention to oxygen sensors that are located in the exhaust system under the vehicle floor pan as they are prone to mud contamination.

R32 GTR's and RB30's

There are other types of oxygen sensors that utilise a heater but have a manufactured housing, which is fitted with a special titania/ceramic probe, which has five layers of alumina at the base of the probe tip. In one of the layers is a heater whose function is to raise the temperature of the titania/ceramic probe and keep it at a predetermined operating temperature. The sensor is arranged in the exhaust system in such a manner that the outer surface of the titania/ceramic probe lies in the exhaust gas flow. The inner surface is, of course, in contact with the atmosphere through the reference orifice. The sensor is activated at high temperatures when the titania/ceramic material is capable of oxygen ion conductivity.