I recently failed inspection due to hi emission readings. I did a tune up and after seeing the wide price range of the 02 sensor I did some research.

My original sensor was 127.00 -190.00 replacement for just the sensor.

I found another O2 sensor for a VW exactly the same with different connectors. Replaced for 39.00 and wala it worked. I hooked up to scope and great signal! fast response time. The part number was the same except for the last 3 digits. In my experience with German companys the last 2-5 digits determines the cable length and connector types. 0 258 003 945 (original) 0 258 003 267 (bought) If someone knows for sure I would love to know.

site:http://www.boschusa.com/AutoParts/FAQs/OxygenSensors/

There are five fundamentally different types of oxygen sensors: unheated thimble 1976-1982, (**heated thimble1982-1997**), planar1997-2004, 2004wide-band and titania. Within each sensor type, sensors vary in the design of the ceramic element, heater element and protection tube design, all of which affect sensor operation.

Wideband: This is the newest design of oxygen sensor and it offers the increased accuracy needed to meet the latest emissions requirements. Unlike all the other types of oxygen sensors, the wide-band sensor can actually measure the air/fuel ratio from 11:1 (excess fuel condition) all the way to straight air (no fuel)! (The ideal air/fuel ratio is 14.7/1.) This improved measurement allows the engine control system to measure the actual air/fuel ratio and eliminates the switching between lean and rich associated with a traditional type of oxygen sensor. These sensors use a planar zirconia ceramic element, so that they heat up much faster than other types of sensors- reducing cold start emissions. These sensors can be identified with having five or more wires. In addition, these sensors are used with the newly developed gasoline direct injection engines. Direct injection engines can use stratified charges, which produce a very lean mixture in the combustion chamber, and these sensors must be used because of their ability to measure from very lean to very rich accurately.



Wire output All Bosch 4-wire sensors have a black wire for the signal, a gray wire for ground and 2 white wires for the heater. Note: the wire colors and functions on non-Bosch sensors are not necessarily the same as on Bosch sensors.
3 wire sensors use casing as signal ground.


Just thought you would like to know

Anthony Bridges