Failed inspection, mystery code + turbo question

J391 · Post by **J391** » 21 Jun 2006, 07:31

Ill start off by saying my new 850 (95' Turbo) failed inspection,
specificaly NOx. I pulled two codes out of socket 2, 435 which
is oxygen sensor slow to respond. Problem is, it has two so how
do I know which one is slow? The other code is 443 and using this
table here:

http://au.geocities.com/ozbrick850/comp ... volvo.html

There is no 443, does anyone know what that is?

Id also like to ask people who have owned both the 850 turbo and
the 960/s90. There is a s90 in the family, and I am finding it to
be a much peppier car, even though it is 180hp vs 222hp. Low end
torque is better (of course due to turbo lag) but the rpms seem
to fly quicker further along on the band. So I was wondering
what peoples impressions were if they have driven both. Im also
wondering how far east your guyses turbo guage goes when in boost.
Mine seems to get into the white but only by say a centimeter. I
also tend to wonder if my tranny (auto) resists kicking down. It
seems to do it from first to second but beyond that, im kinda
wondering if that is culprit.

Anywho... your thoughts would be appreciated.

bryang · Post by **bryang** » 21 Jun 2006, 10:17

I have a subscription to AllDataDIY for my 94 850 Turbo - the description I found out there for 443 is :
4-4-3 THREE-WAY CONVERTER EFFICIENCY

The ECM continuously monitors the Three-Way Converter's (TWC ) efficiency by comparing the signal from the rear Heated Oxygen Sensor (HO2S ) with the signal from the front Heated Oxygen Sensor (HO2S ). When the TWC's efficiency deviates too much, the ECM sets DTC 4-4-3.

Sounds like you have an issue with you O2 sensors. If you go to volvospeed.com and go to the repairs/maintenance section you can find a description on how to replace them.

J391 · Post by **J391** » 22 Jun 2006, 10:55

Thanks Bryang for your response. I posted on the brickboard
to and out of both you were the only one, guess I dont have
much luck with forums. Anywho.. Do you know how I might
find which one is bad? Are they the same sensor so I can swap
them till the code goes away? I have a bit of an exhuast leak
around that area, not sure if that has anything to do with it.

Those two codes were only from A2. So today I checked all the
sockets. Yikes: 213,214,122,435,443,122,235,126,324,413,418
I think im in big trouble with this thing, probably some of those
are minor though.

To get back to the 02 for a sec. I tried searching where the connector
end of the 02 sensor goes, but as Im following it I keep loosing it.
Might you have an idea where they both connect?

THanks again,
Jon

bryang · Post by **bryang** » 22 Jun 2006, 16:52

Jon,
I have never replaced my 02 sensors so I can't help you on replacing them or trying to dertermine which one might be bad... sorry! As far as the codes I had the same issue when I bought my 94 850, all I did was reset them and see if they came back. Most of them didn't, a few did, I wouldn't worry about it just yet. If you need to know what a code means you can post it and I will find out for you... the other option is to get the Haynes or Chilton's manuals, they have the codes as well.

As for forums I have found the volvospeed forum to be much more active than this one, you should try there with your question on which one to replace first. They have a tremendous amount of old posts you can search through and read, read the "how to search", it will help a lot! Whenever I have put out a question at volvospeed I usually get an answer in a few hours and the guys over there really know their cars...

Bryan