Lambda sensor wiring question

[Daz86]

Hi all just a quick question about lambda sensor wiring .

I’ve Gota v70 2.5t and I’m wanting to fit a air fuel ratio gauge wich should be arriving today . But for the life of me I can’t find out via the internet wich wire is the signal wire for a 5 wire wideband lambda bank 1 . On a normal lambda it’s the black wire normally but I can’t find any info regarding the 5 wire

[Clan]

Originally Posted by Daz86

Hi all just a quick question about lambda sensor wiring .

I’ve Gota v70 2.5t and I’m wanting to fit a air fuel ratio gauge wich should be arriving today . But for the life of me I can’t find out via the internet wich wire is the signal wire for a 5 wire wideband lambda bank 1 . On a normal lambda it’s the black wire normally but I can’t find any info regarding the 5 wire

what year? Volvo's lambda sensors are fairly sophisticated and have been digital for quite some time ... You need an analogue 0.1v to 1.0 volt type i guess . When you do fit a gauge which works you will find it boringly around 1 lambda most of the time !

[Daz86]

Thanks for the reply . It’s a 2003 2.5t . I’m positive my cars running lean . I’ve just bought a cheap eBay jobby . It’s got a needle and hopefully will tell me if it optimal rich or lean. This is the eBay item number 401818814525. Probably a load of rubbish and won’t work on my car lol

[cheshired5]

Why not just use cheap diagnostics to view the live fuel trim figures?
No specific tool required.

[Clan]

Originally Posted by Daz86

Thanks for the reply . It’s a 2003 2.5t . I’m positive my cars running lean . I’ve just bought a cheap eBay jobby . It’s got a needle and hopefully will tell me if it optimal rich or lean. This is the eBay item number 401818814525. Probably a load of rubbish and won’t work on my car lol

You will get a fault code if the lambda sensor is not working properly,
have you checked the fuel pressure under load ?


Heated oxygen sensor (HO2S) diagnostic


The front heated oxygen sensor (HO2S) is a lineal type and functions with current control. Therefore it is not possible to measure the signals from the heated oxygen sensor (HO2S) using a multimeter. The rear heated oxygen sensor (HO2S) is a binary type as with earlier heated oxygen sensors (HO2S).
The Engine Control Module (ECM) checks the heated oxygen sensors (HO2S) when the conditions for diagnostics have been fulfilled.


The following faults can be registered by the control module:

Electrical fault in the circuits for the heated oxygen sensors (HO2S) and for the heated oxygen sensor (HO2S) preheating
Adaptation.The control module checks that the long-term fuel trim is not higher or lower than the pre-defined values
Large difference between the front and rear heated oxygen sensor (HO2S) adaptation.The control module checks that the difference between the rear and front heated oxygen sensor (HO2S) adaptation is not too great. The fault may be in the front or rear heated oxygen sensor (HO2S) or the wiring
Heated oxygen sensor (HO2S) dynamics.The control module checks that the changeover period between rich and lean mixtures is not too long
Unlikely signals between the front and rear heated oxygen sensors (HO2S).When the control module registers a rich mixture in the front probe at the same time that a lean mixture is registered in the rear probe or vice versa.

[Daz86]

Originally Posted by cheshired5

Why not just use cheap diagnostics to view the live fuel trim figures?
No specific tool required.

I’ve got a decent code reader that reads live data . Fuel trim levels ae on the low side . I’ve lent it to a mate of mine rally need to get it back

[Daz86]

Originally Posted by Clan

You will get a fault code if the lambda sensor is not working properly,
have you checked the fuel pressure under load ?


Heated oxygen sensor (HO2S) diagnostic


The front heated oxygen sensor (HO2S) is a lineal type and functions with current control. Therefore it is not possible to measure the signals from the heated oxygen sensor (HO2S) using a multimeter. The rear heated oxygen sensor (HO2S) is a binary type as with earlier heated oxygen sensors (HO2S).
The Engine Control Module (ECM) checks the heated oxygen sensors (HO2S) when the conditions for diagnostics have been fulfilled.


The following faults can be registered by the control module:

Electrical fault in the circuits for the heated oxygen sensors (HO2S) and for the heated oxygen sensor (HO2S) preheating
Adaptation.The control module checks that the long-term fuel trim is not higher or lower than the pre-defined values
Large difference between the front and rear heated oxygen sensor (HO2S) adaptation.The control module checks that the difference between the rear and front heated oxygen sensor (HO2S) adaptation is not too great. The fault may be in the front or rear heated oxygen sensor (HO2S) or the wiring
Heated oxygen sensor (HO2S) dynamics.The control module checks that the changeover period between rich and lean mixtures is not too long
Unlikely signals between the front and rear heated oxygen sensors (HO2S).When the control module registers a rich mixture in the front probe at the same time that a lean mixture is registered in the rear probe or vice versa.

I’ve checked the fuel pressure at idle sits at 60psi at the rail witch i think is quite a lot maybe blocked injectors ? I’m unable to check it under load unless change the setup .