Oxygen Sensor Identification

[rasa.us.8qvunjr5gu]

 I recently purchased oxygen sensors for my 2003 Hyundai Santa Fe (V6 2.7L) on eBay.

 I ordered all the four O2 sensors and now I am a little confused as I am not able to differentiate between them. 

The product descriptions are:

1. SKU: 161978

     234-4192

2. SKU:136952

    234-4191

3. sku: 177592

4. sku:177592

If anyone could enlighten me which of these are upstream (L/R) and which are downstream (L/R), that would be really helpful

[cepclpi_ecwztwxzvc]

i can only answer fron a Ford tech-left/right is no difference-front/rear YES-frt. moniters exh. for rich/lean mixture-rear monitores efficiency of converters-NEVER HAVE I SEEN ALL 4 BAD-you likely should be able to identify orentation by number of wires in each sensor-or color of connector.

[long-gone]

Contact the seller and ask them. They should know.

If not then contact the manufacturer and ask them.

[ripsmc]

I always suspect a bad diagnosis when someone is replacing all of the oxygen sensors. You should be aware that there are other things that can cause O2 diagnostic trouble codes.

That would be engine misfires, vacuum leaks, clogged converters, etc, etc, etc.

[mr.elmwood]

4191 is upstream right.

4192 is downstream right.

A simple Google search led me to Amazon with parts references.

The other two will be left.

[omgitlightsup]

---

@ripsmc wrote:

I always suspect a bad diagnosis when someone is replacing all of the oxygen sensors. You should be aware that there are other things that can cause O2 diagnostic trouble codes.

That would be engine misfires, vacuum leaks, clogged converters, etc, etc, etc.

---

I believe O2 sensors are still among the most widely misdiagnosed failures in the auto industry. 

O2 sensors are basically batteries that use the oxygen in the atmosphere to generate electricity. The computer knows only that the sensor is or is not generating electricity; not the reason why. It could be anything from a bad connector to a leak in the exhaust system preventing them from working; or a simple coating of soot (carbon can short out electrical components).

Mechanics like to sell O2 sensors because they're very expensive and can usually be changed in minutes. The only reason that all of your sensors would be bad is because something destroyed them all at once, and if you replace them without finding out what that was, you'll be doing it again soon.

[tony1963]

I have observed a few distrinct characteristics when it comes to oxygen sensors that vary widely according to how the engineer designed the software to function.

• Poor Driveability - I have typically found this on the older Volvo twin turbo engine where the oxygen sensor signal is required to control proper throttle response and turbo boost.  The inline 6 is engineered as two 3 cylinder engines with each set of cylinders and manifolds manages as a unique unit.  The lack of a good sensor signal will result in very erratic performance.

• CEL Only - These vehicles have a programmed default when an oxygen sensor signal goes out of range and will continue to run without any identifiable changes in performance.  

I would not change oxygen sensors unless you have a scan tool to read codes and actual data values, unless you have a mechanical failure like a burned through wiring harness on the sensor.