Oxygen Sensor?

greencupbay · Post by **greencupbay** » 09 Jul 2009, 01:49

....Yes... Me again... I can't figure out where the oxygen sensors are!! I have never messed around with any oxygen sensors and I need help. Firstly, where are both of the front ones and both of the back ones. Second, I assume to test them I just put a multimeter over the head of them? And thirdly, I found these sites that offer 02 sensors and don't take a bite of your wallet:

http://www.thepartsbin.com/catalog/?N=9167&Nr=OR(AND(make:Volvo,model:S80,year:1999),AND(universal:1))&Vi=1733+11886+4294963910&y=1999&mk=Volvo&md=S80

and

http://autopartpro.amazonwebstore.com/9 ... =the005-20

Will these do? I got a little scared because I saw that if they are 'universal' I shouldn't get them.. But I don't wanna spend $130 on that stupid part. I just need to know so I can get this thing fixed. Thanks!

Post by **dcarlson12** » 09 Jul 2009, 14:16

Here are (4) pages printed from VADIS which might help you:
Sorry about the misspelling(sp?) of the word oxygen

As far as testing the O2 sensors, I don't know how to bench test them. Perhaps some one else can chime in.

The way I tested them on my 2000 Chevy Astro was to hook up an OBDII reader made by Autotap which connects to a laptop and which allows one to actually see the O2 sensor cycling. I tried this unit on my S80 but it didn't seem to communicate properly like it did with the Astro. I wasn't having any problems and was only connecting the scanner to check if there were any DTC's prior to going through air care. It worked ok for that but didn't seem to want to work well for the tracking other functions.

mykemac · Post by **mykemac** » 10 Jul 2009, 18:18

the scanner is probably the best way to check the sensor,the voltage should oscillate from 0.1 to around 0.9 v about 8 times every 10 seconds,varying slightly with different cars and voltage,heating the sensor with a torch on a bench test isnt a great method of checking sensor as i heated a bad sensor on the vice and i could vary the voltage with heat from 0.1 to 0.9 v (it had a good internal heater)but still it responded poorly when in the car on the scanner,seems like the ion pump which is the fundamental operation of sensor had become poor ,responsively when in position,hope this helps

greencupbay · Post by **greencupbay** » 27 Jul 2009, 13:30

Thanks for the help so far guys. I have been out of town and not able to work on anything. I really just need to know how to test them on the car with a multimeter because it seems kind of impossible since the things are right beside the Converter. Also, those links that I posted previously of the O2 sensors, I just need to know if those are good sensors to get or not. Thanks again for the numbers and the pics, guys, but I just need to know how to do this. ALLDATAdiy sucks; it is def. no Haynes manual.

Post by **mvsuzr** » 01 Aug 2009, 09:34

You should be able to test the O2 sensor with a multimeter. The hardest thing is finding out where the little guys pinouts are. There are some copies of Volvos VADIS software out there, which is basically their electronic manual. It's inexpensive, and worth picking up. I've not had a lot of luck with it, not sure how to navigate through it, but when you can find things it helps. (Forgot my password, too. Make sure you write it down!)

You really should invest in a scanner.
If you get the right one, it should be easy to check the sensor operation, and you won't have the open connections or burn your hands on a hot engine...

Autotap is a great outfit, very friendly people to talk to, and they have an email newsletter that's really informative. Their scanner looks like it's pretty easy to use.

Make sure whatever you buy can talk to your car, there's a number of different "standards" out there.

I bought a TriCAN scanner from Car Code (http://www.obd-2.com) for about $250. This works on a variety of different vehicles, and he offers free software updates for life. (Some of the other scanner mfrs charge a lot for the extended/advanced software for specific cars, so spend some time researching what you want/need).
This scanner wasn't the easiest to learn, but it helped me pinpoint a problem with my ETM (along with all the help from this forum!).

greencupbay · Post by **greencupbay** » 19 Aug 2009, 23:57

I have been using an OBD II reader to diagnose along with my friend at the shop. I am getting really tired of wasting gas because I can smell it's running way too rich. The OBD reader is only giving me ABS diagnostics when the engine starts to run roughly. I have now replaced the PCV grommet and the MAF Sensor. I just can't seem to get this thing to run right! It's back to the shop I go to get them to read my O2 Sensors. It's free to have done for me. Would a vacuum leak be giving me some problems? I seem to keep hearing a hissing sound under the hood and when the dealership clears everything out and I press the gas pedal, it revs high up and then starts moving. It's just a hunch I have, and I was also wondering if there is a common place for a vacuum leak on these Volvos. Thanks for the comments guys!

Post by **JDS60R** » 25 Aug 2009, 20:34

You can test with a multimeter set to DC volts . You will be measuring between .1 and .9 volts.

Find the O2 sensor and observe 4 wires. Two will be white (the heater) -check them for some resistance to see if heater is broken.

The other two wires are the supply and return of the sensor. I think they are grey and black. Place one side of the meter on a good ground and probe the black and grey wires until you find the voltage. The supply will be about 5 to 12volts and the other is the return you want to measure the .1 to .9 DC volt cycle Many of the turbo models do not cycle as much as the non turbo models that were desribed well above. They will seem flat until you rev the car. This is by Design by Volvo - The turbo ECU's are focused around always providing a constant air/fuel ratio. This must change when you accelerate so you will see the voltage change.

Observe the meter and rev the motor (take all necessary safety measures needed) you should see an instant and noticable change in the voltage value. Keep in mind this is much easier to see on an anolog meter (needle) but can be seen on a digital meter is you watch closely.

It is ok to drink but always do it after the diagnosis as you will be near some hot and sharp things.

Good to have paper clips to straigten out and use as backprobe at the sensor connectors as they must remain plugged in during testing. I find the correct wire, back probe it and tape the paperclip and test lead together to the harness so i can face the meter towards the interior of the car while I rev it.
I observe it through the windshield (well - i used to - I have a OBD2 reader with plotting so I can watch the cycles )

Good luck
John

greencupbay · Post by **greencupbay** » 26 Aug 2009, 00:11

That is wonderful info. The only problem is that the two "back/universal" O2 sensors are above (nearest the cab of the car) the catalytic converter, so the converter has to be taken off in order to get to the O2 sensors. Are you suggesting that I am able to test from somewhere else OTHER than where the O2 sensors are placed? I would be able to test them from the tail-end wires of the O2 sensors (preferably from the engine/cab)? Just as long as I can test them somewhere other than the O2 sensors themselves.

greencupbay · Post by **greencupbay** » 25 Mar 2010, 17:06

I have fixed the problem. Just FYI from the Volvo Mechanics, if you get a code for your O2 sensors, both front and rear, than chances are that it's your MAF (mass air flow sensor), but if you get only one, front or rear, than chances are that it's your O2 sensors. I bought my front O2 sensors (bosch) off ebay as they had the best price. It fixed my problem and my car runs well now. Thanks to everyone for their help!

Oxygen Sensor?

Where is the Oxygen Sensor and How do I test?