OBDII : LONGFT1 -15% at idle ( Car running rich )

[LvR]

Found a picture of the O2 Sensor and the plug has 4 pins from what I know this means narrow band

No it doesn't

 

[biomecanoid]

No it doesn't

I thought that wide band O2 sensors had 2 signal wires instead of 1 for narrow band

 

[LvR]

Sometimes but not always ................

This is why I am questioning people commenting on single figure O2 voltages you supplied earlier - they seem to be under the impression that its not an O2 but rather an A/F sensor

 

[biomecanoid]

Sometimes but not always ................

This is why I am questioning people commenting on single figure O2 voltages you supplied earlier - they seem to be under the impression that its not an O2 but rather an A/F sensor

OK then how to I make sure which is which ?

 

[LvR]

Easiest if you dont know the spec of the thing - Post either a log of the voltage or a graph while its idling.................. fast swings like a sinewave is a simple O2

 

[biomecanoid]

Easiest - Post either a log of the voltage or a graph while its idling.................. fast swings like a sinewave is a simple O2

I can make a video showing the data. My OBDII does not log or graph data. I have the Creader 3001

 

[LvR]

Video of the B1S1 or upstream "O2 voltage" is fine for now

 

[biomecanoid]

You mean O2S11 and O2S12 ? That's how my OBDII names them.

 

[LvR]

Dont have a scanner like yours - I have Autel etc etc etc so I am going to guess O2S11

 

[biomecanoid]

SPARKADV

 

[biomecanoid]

Fuel Trim and O2 Sensor videos

 

[LvR]

OK - forgive me for being honest but that scanner is completely useless when trying to chase real-time variations ....................

There is a ton of mismatch in the sampling frequency of individual parameters ...........

Id say spend money on a decent scanner first before you chase any phantom issue you may not even have.

 

[biomecanoid]

OK - forgive me for being honest but that scanner is completely useless when trying to chase real-time variations ....................

There is a ton of mismatch in the sampling frequency of individual parameters ...........

Id say spend money on a decent scanner first before you chase any phantom issue you may not even have.

Oh well that's what I have now. I would like to order the BlueDriver:

BlueDriver Scan Tool | BlueDriver

www.bluedriver.com

But even if I buy it now it will take a long time to arrive.

 

[biomecanoid]

So no conclusions can be drawn from the above photos and videos ?

 

[LvR]

So no conclusions can be drawn from the above photos and videos ?

I'd say you have a O2 sensor not a wideband A/F sensor.

Other than that ........... imo no.

LTFT is a direct reflection of the ability of the ECU to keep the engine operating as close as possible to the factory desired maps - you may not like the slow variations and fairly big number seen on the LTFT, but it's quite possible that it's 100% normal for the current mechanical state of your vehicle.

If you have a STFT oscillating around 0 it's a good indication the ECU is in control of emissions and most importantly the engine is NOT running either rich or lean at all.

Also - you need to compare apples with apples - if the STFT is monitored and to be used for evaluation then the mechanical and electrical load on the engine should be kept constant - in your videos you can hear the eg fans kicking in and out and that WILL cause a change in STFT (via the O2 sensor voltages and the ECU compensating for load)

 

[biomecanoid]

I'd say you have a O2 sensor not a wideband A/F sensor.

Other than that ........... imo no.

LTFT is a direct reflection of the ability of the ECU to keep the engine operating as close as possible to the factory desired maps - you may not like the slow variations and fairly big number seen on the LTFT, but it's quite possible that it's 100% normal for the current mechanical state of your vehicle.

If you have a STFT oscillating around 0 it's a good indication the ECU is in control of emissions and most importantly the engine is NOT running either rich or lean at all.

Also - you need to compare apples with apples - if the STFT is monitored and to be used for evaluation then the mechanical and electrical load on the engine should be kept constant - in your videos you can hear the eg fans kicking in and out and that WILL cause a change in STFT (via the O2 sensor voltages and the ECU compensating for load)

The car was idling, I don't know what else I could have done to keep the engine running steady. I guess it was a hot day and the fans where kicking in.

 

[LvR]

The car was idling, I don't know what else I could have done to keep the engine running steady. I guess it was a hot day and the fans where kicking in.

No use shouting at the messenger.

I am stating facts only.

Its you (and some other here too) with the idea that you need to address something on the fueling or wherever system on the engine while using a tool not designed for the job and also without detailed engineering knowledge (I don't have that either but fuel maps and control on modern vehicles all obey the OBD standards).

Somebody way earlier in the thread already suggested there is effectively nothing wrong and to drive it till there is a MIL reported and I agree.

On a modern vehicle, you better have the proper knowledge, skills and tools to fault-find else you are wasting your time because the ECU will be looking after the engine and will start shouting at you soon as the engineering team can make it do so

 

[biomecanoid]

No use shouting at the messenger.

I am stating facts only.

Its you (and some other here too) with the idea that you need to address something on the fueling or wherever system on the engine while using a tool not designed for the job and also without detailed engineering knowledge (I don't have that either but fuel maps and control on modern vehicles all obey the OBD standards).

Somebody way earlier in the thread already suggested there is effectively nothing wrong and to drive it till there is a MIL reported and I agree.

On a modern vehicle, you better have the proper knowledge, skills and tools to fault-find else you are wasting your time because the ECU will be looking after the engine and will start shouting at you soon as the engineering team can make it do so

I was not shouting. I do remember that both short and long fuel trim were exactly 0, plus I have CAT_RDY INC and black soot coming out the exhaust which could be what made the catalyst inefficient. The CAT_RDY INC is there for about a month isn't that a problem ? how will the car pass emissions test ?

 

[LvR]

I was not shouting. I do remember that both short and long fuel trim were exactly 0, plus I have CAT_RDY INC and black soot coming out the exhaust which could be what made the catalyst inefficient. The CAT_RDY INC is there for about a month isn't that a problem ? how will the car pass emissions test ?

This is the problem:

Both STFT and LTFT cannot possibly ever be 0 at the same time for any extended period - sure LTFT can be 0 for hours or days, but STFT, due to the presence and operation principles of the upstream O2, must always be cycling in small values, either positive or negative, around 0.

So ..................... what is it you are trying to achieve? ................ constant 0 STFT? ............. never going to happen no matter what if the O2 and ECU is working as designed.

CAT_RDY INC ................ who knows EXACTLY what the requirements of the testing conditions found in this Daihatsu ECU are? .

If you currently without the proper logging tool want to chase a complete unknown then I don't know .................. nobody here seems to have access to the engineering info you require.

As we said before - the ECU is quite capable of telling you all about your cat if it's failing - if, in a month's worth of driving now under various conditions you have not received a MIL on the dash stop worrying.

 

[biomecanoid]

This is the problem:

Both STFT and LTFT cannot possibly ever be 0 at the same time for any extended period - sure LTFT can be 0 for hours or days, but STFT, due to the presence and operation principles of the upstream O2, must always be cycling in small values, either positive or negative, around 0.

So ..................... what is it you are trying to achieve? ................ constant 0 STFT? ............. never going to happen no matter what if the O2 and ECU is working as designed.

CAT_RDY INC ................ who knows EXACTLY what the requirements of the testing conditions found in this Daihatsu ECU are? .

If you currently without the proper logging tool want to chase a complete unknown then I don't know .................. nobody here seems to have access to the engineering info you require.

As we said before - the ECU is quite capable of telling you all about your cat if it's failing - if, in a month's worth of driving now under various conditions you have not received a MIL on the dash stop worrying.

The CAT_RDY INC is not a state emissions test fail ? This should not be addressed ?