Volvo 850 O2 sensor woes...

Vanillagorilla · Post by **Vanillagorilla** » 18 Jan 2012, 08:34

Hello all,

So I posted a question recently about my O2 sensor light being on, and having a difficult time finding the right O2 sensor for my B5252 (Canadian) Volvo 850 non-turbo. After a great deal of research and some valuable tips from some of you, I found that the replacement part was a NTK 25005 sensor, which I found online for $93 and replaced this weekend. I disconnected the battery to do this repair, and when I started the car the light had cleared. I've been driving it for 3 days without incident, and this morning the light came back on. The car runs fine, and has always been running fine. I recently did a tune up, and replaced some aging ignition parts, so I am sure that I am getting a good spark. The sensor is up-stream from the catalytic converter (some of you may think that I should have two O2 sensors, but the B5252 engine only has one). Could my catalytic converter be clogged? Any help will be greatly appreciated!

Thanks in advance

Post by **tjts1** » 18 Jan 2012, 09:12

If you have a persistent misfire or are running abnormally rich or lean you will get a CEL or in your case O2 sensor light even with a good sensor. What kind of spark plugs did you use in your tune up?

Vanillagorilla · Post by **Vanillagorilla** » 18 Jan 2012, 10:09

I used NGK G-power plugs...

Vanillagorilla · Post by **Vanillagorilla** » 18 Jan 2012, 10:13

I used NGK G-power plugs...

Vanillagorilla · Post by **Vanillagorilla** » 18 Jan 2012, 19:05

So I have a new update to this issue... I just disconnected the battery and the light went away again. Is it possible that my catalytic converter could be clogged? I live in Vancouver Canada and our emission standards are quite high. I am due for an emissions check in May, and I need to get this resolved well in advance to be safe. Any advice will be appreciated.

Post by **jmmxc** » 19 Jan 2012, 06:51

Could you indicate which code(s) you are getting when your CEL is on?
If you are using a scanner, verify if you are either getting a single or multiple codes.
This would help narrow down the issue, there may be several codes related to the emission problems due to O2 sensors and cat.
jmmxc.

Vanillagorilla · Post by **Vanillagorilla** » 19 Jan 2012, 18:29

I'm not getting a check engine light... On my car I have a warning light for o2 sensor.