Oxygen sensor/lambda

[Stian_P 0 1 Cars]

Hi.

 

Does anyone know if there are any differenses between oxygen sensors? I`m thinking of performance, and longevity of the sensors themselves. I bought a universal type for my cat equipped gti a few years ago, and I`m thinking its on its way out allready, the car is having the same symptoms again. It`s harder to start, and the exhaust is smelling a lot more than it used to. I allso think it`s using more fuel. 

My car has the XU9JAZ engine.

 

[DamirGTI 323]

Yes , there is differences ... not as important on an old car such as 205 , however very important/sensitive for new cars .

 

Buy quality brand sensors - Bosch , Denso , NGK/NTK .. avoid all the rest unknown stuff .

 

It's reasonably easy to test the O2 sensor function with the multimeter .. sensor heater element is easy , ignition ON and feel/touch the sensor tip with you're hand/fingers if it's heating up (it should) .

 

Common problem on later 205's with the XU9JAZ engine is water/moisture ingress inside the O2 sensor wiring connectors , as it's way down below the chassis leg .

 

Additionally , you have "self diagnosis" function on a XU9JAZ engine (green 2pin connector near the fuel filter) , so you can pull out fault codes , not as much of them but better than nothing .

 

D

[welshpug 1,621]

Most 4 wire units are much the same, main differences is the wattage of the heater element, the length of the lead and the style of plug/s if included.

[Stian_P 0 1 Cars]

4 hours ago, DamirGTI said:

Yes , there is differences ... not as important on an old car such as 205 , however very important/sensitive for new cars .

 

Buy quality brand sensors - Bosch , Denso , NGK/NTK .. avoid all the rest unknown stuff .

 

It's reasonably easy to test the O2 sensor function with the multimeter .. sensor heater element is easy , ignition ON and feel/touch the sensor tip with you're hand/fingers if it's heating up (it should) .

 

Common problem on later 205's with the XU9JAZ engine is water/moisture ingress inside the O2 sensor wiring connectors , as it's way down below the chassis leg .

 

Additionally , you have "self diagnosis" function on a XU9JAZ engine (green 2pin connector near the fuel filter) , so you can pull out fault codes , not as much of them but better than nothing .

 

D

Do you know if its possible to change the connectors to a newer type thats waterproof? Or maybe its possible to de-pin the connectors? Then I can allso change some of the wiring if its corroded. 

 

Guess I Just have to fork out for a new Bosch sensor, they are a bit on the pricey side. But you get what you pay for I guess. 

[Anthony 1,000]

3 hours ago, Stian_P said:

Do you know if its possible to change the connectors to a newer type thats waterproof? Or maybe its possible to de-pin the connectors? Then I can allso change some of the wiring if its corroded. 

 

Guess I Just have to fork out for a new Bosch sensor, they are a bit on the pricey side. But you get what you pay for I guess. 

 

You can remove the connectors/pins and replace with a more weatherproof connector - JPT, Superseal or whatever the latch type used on late 90's onwards PSA lambdas are called - but you'll likely run into issues with corroded wire as Damir says.  You really want clean wire to crimp new terminals onto, and ideally use a proper crimping tool for the terminal design you're using (but you can make good crimps with a little patience without).

 

Bosch sensors are comparatively expensive, but they are worth it over the generic no-names aftermarket ones that never seem to last and can cause odd running issues.  You can with a little lateral thinking find suitable 4 pin Bosch lambdas aimed at various 90's or early 00's era cars that have a manufacturer proprietary connector fitted cheap as NOS or as part of a clearance on eBay, Amazon etc - if you find something otherwise suitable, simply chop off the connector and replace with a suitable one to match the lambda plug on the engine loom.

[DamirGTI 323]

Try universal 4 wire Bosch sensor : 0 258 986 506 ... comes with nice sealed connector and special "screw on" tubes for connecting the wiring .

It's rated for 160.000Km's replacement interval , costs usually around +/- 60 EU ... i fitted a fair few to even more modern/newer cars (which tend to be O2 sensor picky) and so far no complains .

 

Or as Anthony says , browse the web for the OE style sensors with OEM style connectors for older Peugeot's/Citroen's from the 80's/90's , say like for the Peugeot 605 2.0 l . Demand for 605 parts is pretty low so you can find bargain priced stuff , same as Citroen XM and a few others .

Connectors on the O2 sensors for the above cars tend to be different colour than for the 205 ones and with little longer wiring , but otherwise they're the same type of sensors and will plug in directly on the 205 O2 sensor wiring harness .

 

If you're engine burns oil , or if you're using some zinc rich oil type or adding lead fuel additives that can shorten O2 sensor life considerably too .

 

D

[Stian_P 0 1 Cars]

Thanks guys. I'll see if I can find some connectors to change the originals with, I will also check the wiring for corrosion when Im at it. 

 

Thanks again for the help, much apreciated. 

[Richie-Van-GTi 70 2 Cars]

Symptoms sound more like a faulty temperature sensor to me

[Stian_P 0 1 Cars]

I have installed Bosch sensor : 0 258 986 506 as Damir recommended, and the car starts much better now. But now the K-light is lit when I`m driving at a steady speed, if I de-clutch and let the engine idle a little bit it goes away. If I accelerate it dosent come back, only when at a steady pace. I also noticed quite a bit of blue smoke from the exhaust, specially at idle. It goes away when I`m driving away. The smoke looks to me to be the valve stem seales(?), but could this also be the culprit of the K-light? 

The car drives as usual, dosent seem to be down on power or anything else.

[Stian_P 0 1 Cars]

On 9/16/2022 at 8:23 PM, Richie-Van-GTi said:

Symptoms sound more like a faulty temperature sensor to me

This will be my next port of call, if it`s not the O2 sensor causing problems. 

[DamirGTI 323]

Blue smoke is oil .. grey/black is fuel (rich mixture) .

If it's burning oil that'll foul O2 sensor reading , and in the long run and if excess will damage it permanently .

 

Did you connect all the O2 sensor wires as per the wiring instructions supplied inside the O2 sensor box ?

 

Read the ECU fault codes , all you need to do is earth green 2pin diagnostic connector , an switch to activate/deactivate diagnostic mode , and count the MIL lamp flashes (they're just two digits codes on a 205 , easy to read/count) .

 

My assumption is (if the O2 sensor wiring is connected properly) , that this new working sensor now detects less oxygen in the exhaust but it's false reading less because of the oil fumes present in the exhaust .

 

D

Edited September 18, 2022 by DamirGTI

[Stian_P 0 1 Cars]

24 minutes ago, DamirGTI said:

Blue smoke is oil .. grey/black is fuel (rich mixture) .

If it's burning oil that'll foul O2 sensor reading , and in the long run and if excess will damage it permanently .

 

Did you connect all the O2 sensor wires as per the wiring instructions supplied inside the O2 sensor box ?

 

Read the ECU fault codes , all you need to do is earth green 2pin diagnostic connector , an switch to activate/deactivate diagnostic mode , and count the MIL lamp flashes (they're just two digits codes on a 205 , easy to read/count) .

 

My assumption is (if the O2 sensor wiring is connected properly) , that this new working sensor now detects less oxygen in the exhaust but it's false reading less because of the oil fumes present in the exhaust .

 

D

It smells like its burning Oil, so I guess its the valve stem seals. If I rev it up, the k-light goes away for a few seconds, and then comes back on. 

I found a guide online from bosch, two White wires are 12v to heater element, Black wire is signal wire and grey is sensor ground. I dont have the grey wire, so I grounded it to the alu plate where the ignition amp is mounted. 

I read the o2 values from signal wire with engine running, it read between 0.08V and 0.1V regardless of rpm.

 

How do I activate diagnostic mode?