Hello, I finally got around to checking out the O2 sensor in y daughters 2004 Jag S Type 3.0; its between a rock and a hard place and I had to remove the oil filter to relieve some the pain in the space. The threads and videos are right on point by showing that the upstream driver side is always the culprit and it looks pretty bad.
Market price has been between $90 - $160, does anyone know exactly where I can purchase a working O2s that beat those prices?

 

I've copied this from your Intro thread for advice from US members with the same model.

Graham

 

Given the tight access and the fact that the O2 sensor is critical to proper fuel trims, this is perhaps not the best place to scrimp on quality... Denso, Bosch or Morotcraft are known quality engine management components... please don't get no-name, off-brand parts for this particular application.

 

Er... not always - unless the code says so! (What's the code you have?)

Forum sponsors sell 'em...

 

I have decided to test the O2 sensors just for kicks: Doc. attached.

 

The $64 Question:

Why exactly are you checking out the O2 sensor? Do you have a fault code? If so, please let us know the exact code. It's usually a single letter followed by 4 numbers, such as P0430.

If you have a code for one O2 sensor, and are reluctant to gamble on a new sensor, you can swap the sensor from side to side and see if the fault follows.

 

When needing to understand the cost of parts and variations available I go to 2 sources: rock auto dot com and amazon I'm not endorsing either one, rather its just a good way to quickly see what's available and the costs comparison for everything from bottom end cheap -to- OEM.

 

I am working on a 2004 s type 3.0, reg. body and a mechanic diagnostic scan revealed a HO2S code and he said that it is bank 1

 

Shame he didn't give you the exact code.

It could have been a fault code for the sensor heating circuit. The heater quickly warms up the sensor after a cold start, so it can start working sooner. If the heating element is burned out, your only option is to replace the sensor.

The other possibilities are related to the actual O2 sniffing portion of the sensor. You could have a fault code for reading high, reading low, slow response, etc. Sometimes the fault is the sensor itself, but it can also be an external fault such as an exhaust leak upstream of the sensor. Troubleshooting varies based on the specific fault code.

Also, did he specify if it was the upstream or downstream sensor? The upstream sensor monitors the raw exhaust entering the catalytic converter, and signals the computer to adjust the air/fuel ratio. The downstream sensor monitors the efficiency of the cat. You've got relatively dirty exhaust entering the cat, and if the cat is functioning properly, the downstream sensor should see much cleaner output.

With so many variables, you're going to be flailing around and making expensive guesses without the exact fault code. If you don't want to take it back to that shop, most auto parts stores will read the codes for free. The late model O2 sensors aren't cheap. That's why I previously recommended swapping the sensor from side to side, to see if the fault follows.

 

+1 go to one of the auto stores and get the actual code number before going too far.

 

I recently got upstream Denso O2 sensors for my V8 car on Ebay for a lot less than at NAPA. Replace the pair if there are two of them, if need be. They are very important for the engine to run properly. You could get cheaper brands, but the cars came with Denso sensors. All the third party electronics I've noticed on my car are Denso. That's one of the reasons the S Type is so dependable, I think.