What Style Of O2 Sensor Does The 2001 N/a V70 Use?

[own6volvos]

I am trying to figure out if the front sensor on our 2001 v70 is screwed, but coming into problems actually testing it. Its a 4 wire sensor, where the ground for the sensor is supplied from the wires instead of the exhaust (or so I think). This leave 2 black wires for the heater, and then one grey wire and one blue wire. Now hooking up a multimeter to these the thing will first screw with my autorange in the low settings, then just stop working and not do anything be the time i switch it up to a higher voltage range.

This brings me to the 2nd question, do the newer Volvos use standard o2 sensors, or are they some wacky resistive style units? I have seen some 4 wire universal ones up on ebay for this same make and model, which leads me to believe they are the same.

All of this is to trace back why the emmisions service crap comes on every other day, and sometimes just turns off completely. The dealer keeps telling us that whenever they scan it, nothing shows up, and it seems to always come up when not at the dealer. With a standard obd2 scanner it pulls up the P420 or cat fault, but a wacky o2 sensor could also mkae that go. Its gas mileage went from 30-32 down to 26 which also points to the o2 sensor. Since we aren't really a money tree, throwing cash at items that may or may not be the issue isn't really an option unless they are cheap parts. I have a few brand new 4 wire normal style o2 sensors laying around, but have been worried about screwing up the car because it took some wacky resistive unit or custom WB thing.

To add to the wackyness, here is the Vadius tidbits on this

Front Sensor:

The measurement range 0-2. The normal value is λ=1. When the fuel air mixture is rich λ<1. When the fuel air mixture is lean λ>1.

#A24(#A24)Signal (+)

Front heated oxygen sensor (HO2S) signal (+)-λ= 0.95 V>700 mV

λ= 1.10 V<200 mV

#A41(#A41)Signal (–)

Front λheated oxygen sensor (HO2S)-λ= 1 when the current is approximately +0.2 mANegative current when the fuel air mixture is rich. Range: [-12 mA, +12 mA]

#A42(#A42)Signal (+)

Front λheated oxygen sensor (HO2S)-λ= 1 when the current is approximately +0.2 mAPositive current when the fuel air mixture is lean Range: [-12 mA, +12 mA]

Rear sensor:

Measurement range 0-5 V. Operating range 0-1 V. The normal value when the engine is running under an even load is ≈ 0.6 V.

Anyone care to translate that?

[merlin390]

they use a bosch 4 wire O2 Sensor.

go to the bosch home page and poke around some

[Guest Guest]

Well, there seems to be a few different styles of 4 wire sensors that Bosch makes. Also, under the vehicle part finder thing, there is no section for o2 sensor for a 2001 v70 n/a

[own6volvos]

Me^^^

[starfish]

That symbol is the lower-case Greek letter lambda. The Swedes got fancy here and used it to describe stoichiometric air to fuel ratio. A lamda sond is the oxygen sensor.

I'm not 100% sure what exactly you are trying to state about your problem but to me it seems like you have a catalyst efficiency failure code. Many times this is not caused by a bad O2, but blown out exhaust manifold gaskets.

[own6volvos]

That symbol is the lower-case Greek letter lambda. The Swedes got fancy here and used it to describe stoichiometric air to fuel ratio. A lamda sond is the oxygen sensor.

I'm not 100% sure what exactly you are trying to state about your problem but to me it seems like you have a catalyst efficiency failure code. Many times this is not caused by a bad O2, but blown out exhaust manifold gaskets.

←

Its more of a "this problem won't go away", but how do I fix it without buying brand new dealer parts.

I am curious if a standard 4 wire sensor similar to what the 850's use, and lots of other cars will work spliced in.

[Bay13]

http://www.fcpgroton.com

get the OEM O2 sensors, I've not seen many positive results with the shop around and jury rig method.