Replace the Oxygen Sensors on an E36 (1991-1999) 3 Series BMW
1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999 BMW 3 Series Models
BMW 3 Series Includes: 316, 318, 320, 323, 325, 328, 330 and M3 .
The oxygen sensor is one of the most important elements of the modern fuel injection systems. A finely tuned fuel injection system with an oxygen sensor can maintain an air/fuel ratio within a close tolerance of .02 percent. Keeping the engine at the stoichiometric level (14.6:1 air/fuel ratio) helps the engine generate the most power with the least amount of emissions.
The oxygen sensor is located in the exhaust system of the engine, and senses the oxygen content of the exhaust gases. The amount of oxygen in the exhaust varies according to the air/fuel ratio of the fuel injection system. The oxygen sensor produces a small voltage signal that is interpreted by the electronic control unit (ECU) of the fuel injection system. The ECU makes constant adjustments in fuel delivery according to the signal generated by the oxygen sensor in order to maintain the optimum air/fuel ratio.
View the full tutorial at PelicanParts here: BMW 3 Series (1991-1999) Oxygen Sensor Replacement DIY