Can you just drop one in a wideband O2 in place of the old one on these cars, or do they require a compatible fuel management computer? My car has LH 2.2

 

afaik, any standard bosch style o2 3-wire sensor with the right size threads will work, you'll just need to splice the volvo connectors onto it.

I'm pretty sure LH2.2 and 2.4 used the same o2 sensor, and its pretty much the same as the one in my 1996 bmw motorcycle, or my 1991 mercedes 300e, just each application has its own wiring harness.

 

Well that's great news. From what I read their advantage is higher accuracy. It may help stabilize my rough idle, but still Won't help find the actual problem. If it helps, that is good by me.

 

Joe, it isn't as simple as all that. A standard (narrow band) O2 sensor produces an analog output for the ecu. A wideband produces a digital signal. It is certainly possible to run fueling from a wideband, but you need the entire setup including a wideband module that, along with providing you a precise readout of afr's, will create a synthesized analog output for the ecu. So, rather than simply installing a WB and somehow wiring it into the cable going to the ecu, the signal must go from the sensor to an aftermarket module and then the synthesized signal goes to the ecu. BTW, even an older 1 wire O2 will work w/ later Volvos. The other 2 wires are simply heater wires which allow the O2 to get to operating temp faster. A wideband will have at least 4 wires and as many as 6...or more.
Additionally, wideband sensors are a bit more delicate than stock narrow bands. A narrow band benefits from being as close to the output of the turbo as possible. Do that with a WB and you will cook it. Check this picture of a downpipe. Notice there are two bungs and two sensors. The one closest to the flange that connects to the turbo was originally an NB sensor while the one downstream is a WB. That's because I did not trust the WB to produce an accurate signal for the ecu. After gaining confidence, I swapped out the NB and put an EGT in its place.
Early WB's were bulky with separate gauge, module and sensor but now, the systems are much smaller and cleaner like the one I have now made by PLX...
As well, with this setup, the one gauge can actually replace several as it can measure afr's, boost, oil pressure, oil temp and egt. Just needs a separate module for each additional function and then they get daisy chained together.

 

I think you have digital and analog swapped in that description? standard narrowband O2 output is either high or low, and swings back and forth with a duty cycle as the engine goes above/below stochaic. the wideband sensors output a continuous voltage over a wider range not just high/low, this would, in my book, be more analog.

(I'm coming from a computer and electronics engineering background, not mechanical/automotive)



and sorry, I didn't connect the dots when you said wideband in my earlier response. ALL those sensors I described are narrowband.

 

Old post, but a similar question, with an added twist. I received a 4 wire o2 sensor instead of a 3 wire for my old 89 740. I know how to properly connect it, but what's the chance the 951 ECU would be able to make use of the extra input? 951s were first used in 93 vehicles, and some of them had OBDII, which may mean an upgrade to the 951 also. Or, do you think I should get a 3 wire o2 sensor?

 

OBD-II wasn't in any Volvos until MY 1996, the last US 940 was MY1995.

I would get the correct O2 sensor, I don't think the 4 wire kind can be made to work.

 

I have used a Mustang v8 O2 sensors, don't remember the exact number... easy splice job.

 

key is to splice them well. I've seen more than a few spliced O2 sensors where the splices didn't age well. fixed the VW/Audi I4 in my kid's vanagon westie, someone did it with typical red cheap inline crimp splices. I used better splices with dielectric grease inside, and liquid tape + shrink-wrap outside.

 

Thanks for the replies fellows. I see that the chip in the 951 ECU does have an A/D converter, so I should be ok even if the o2 sensor is a wideband.

 

good luck with that. I'll frankly be quite surprised if it works, regardless of what the chip has in it. No B230F(T) was supplied with wideband OX sensors, so the odds of their being programming in the ECU to handle them are between slim and none.

the CTS and MAF are both analog inputs, which are fed into A/D converters, for what that's worth.

 

Well, I guess I need to find out if this Tru-Tech (SMP) SG36T is narrow band or wide band, before proceeding. First I'll try making better connections with the one that is on it, the one that ran well until I got the ECU wet. I likely got my connections to the o2 sensor wet too. I'd have probably been ok if it wasn't for that big truck going through the waterhole in the opposite direction! He left quite a wake!

 

Couldn't find anything definitive, but one good application chart I found listed the SG36T as being for mostly mid to late 80s vehicles, the chart stopped at 88 and listed some prior years of Volvo 740. Should be a narrow band.

 

the correct Ox sensor is a Bosch 3-wire. 2 wires are for the heater, the third wire is the signal. They last at least 60K miles.

 

Hi,
I have replaced on LH2.2 (740gle) original pn: 0 258 003 009 with 0 258 003 942 that has Bosch pn 13942 on the box. This is supposed to be 92 V8 Mustang sensor?
These different LH systems have different fuel pressure, you have to buy correct fuel pressure regulator and injectors are also not interchangeable. So i actually wonder if someone knows what is precise replacemant O2 sensor pn for LH2.2 system?

 

https://www.fcpeuro.com/products/jag...t-3-wire-13957

 

Hi,
Where did you get the reference for the pn?
Thanks

 

I looked up the appropriate O2 sensor for my 87 240 (LH 2.2) on fcpeuro and that was the bosch OE direct fit version.

 

Heres some others that supposedly work right: https://www.volvoclub.org.uk/faq/Eng...placements.htm

I got one of the Bosch 13913 off ebay real cheap. Since the old girl is running just fine as is, I've not changed it.

New Bosch Oxygen Sensor 13913 for Ford Lincoln Mercury and Merkur 1984 1989 | eBay

The seller doesn't list this as for the 740, but the above link does, one can see the connector is different, but it can be cut off and wired in.

What's important is the signal from the 02 to the ECU. It's the Ecu that sends the signal to the injectors, not the o2 sensor. Your 13942 ought to work fine.

 

I'm trying to think of how many spliced on O2 sensors I've replaced due to corrosion on crappy crimped splices. and the high temperature wire they use doesn't solder well.

thanks, but $50 or 60$ for the right Bosch sensor with the right plugs on it is worth every cent, you replace these maybe every 100k miles under normal conditions.