Technical Excess emissions

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Technical Excess emissions

ct3im

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Hi all , escuse my bad English, I believe someone could help me , have one punto MK1 1.1 he lost in inspection , excess emissions.
Using IAW , when start motor the lambda correction is 1 , past some seconds the value goes down , 99,98,97…..70 . I have tried other lambda,catalist ,MAP ,Canister , injector body , ECU from a working car and same result , my mechanic don’t have more ideas , I am desesperate.
Any help is appreciate!

Br Hugo.
 

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do you have the actual emission test results? knowing what is high, whats low and whats in spec should give some idea of what's going on
Hello, Thank you for your answer , you could check the picture , the lambda correction must be 1 but at the moment is 0,75 , that mean the misture is very rich . If i press a little and quickly at acclerator , the value goes to 1 and 10/15 seconds left start count down , 99,98,97,96…..and stay arround 70/72 .
For example , if i remove lambda from circuit , this value goes to arround 135 , this mean a poor misture.
 
Yes but on the emissions test itself, what did the machine at the testing facility give - they would have measured Hydrocarbons (HC), Carbon Monoxide (CO), Lambda (O2) and oftentimes Nox as well.. What did it actually fail, one of those, all of those. Its much easier to diagnose what the issue maybe from the actual results.

Different issues cause different emissions issues so actual results usually help rather than just going on the Lambda which only give you part of the story.

How do the spark plugs look? Do they indicate a rich mixture? what temperature is the ecu showing when the stat opens and the rad fan comes on, it could just be the coolant temp sensor is failing and its constantly running in a rich warm up mixture - when you start the car cold does the lambda show as open loop and change to closed loop once warmed a bit and stay in closed loop?

Could be weak coil or coils, good enough to run but not strong enough for complete combustion.

Could be leaky injector or injector seal.

Quite a few other things possible but you can eliminate quite a few just by looking at the actual results from the test equipment rather than just going by the Lambda signal, and remember its only a narrowband sensor so all its really doing is telling you if its rich or lean, not how rich or lean.
 
For now I only have some answers , I don’t have any values HC,CO or O2 , at inspection they only said have to much emissions , last year I lost 4 times and at last time i have the help from the inspector (I believe he help-me).

In February I have the anual inspection , and I know something is wrong because the lamba correction the value is arround 72 and must be 1 because I have measured in other same model car.
I have readed your last post and I have changed the coils but same result.
Three day ago I have replaced the switch fan sensor.
The temperature (blue sensor) is working because using IAW software I could measure the temperature.
In this car I have previously replaced all injector body , replaced ECU , replaced Lambda (removed from another working car) replaced the canister and respective valve , replaced the MAP sensor , and same problem.
Today based in your last message I do the mesure and apparently the conclusion is , with the motor cold , I start engine and the lambda shows open , and when temperature is arround 45C lambda shows close , could be coincidence because I have this test only one time , but , during the period the lambda is open , the lambda correction value is the desired , the 1. Tomorrow with engine cold I repeat again this procedure to determine if was coincidence or not.
One last procedure I have done based one factory manual is the readaptation modules , I have disconnected the blue temperature sensor, MAP sensor and trotle potentiometer in injection body and start running (have done 2km) when arrived , disconnect the battery and past 5 minutes reconnect itens previously disconnected , reconnect battery and put motor working , when hot the fan arm , i have done 3/4km km. But this don’t solve my problem.
I fact i don’t know more what to do. The strange is the car works fine , apparently there is no problem. Start well , run well.
About sparks color , if i run the color is normal , but if only put motor working for a long period with moisture rich probably the sparks goes black.
This car I think don’t have the thermostat.
 
I understand your point of view , I forgot to said , the catalytic was replaced from other car without problem.
The question is , the lambda is pre catalytic , if lambda is giving (reading) abnormal values (wrong moisture?) pre catalytic , first steep is solve this.
When solved and lambda correction reading the value 1 , and if continue with gas problems , in that case i accept if someone tell me the problem is the catalytic.
 
First step ...fix cooling problem so engine runs at correct temperature.
 
I understand
First step ...fix cooling problem so engine runs at correct temperature.
your point of view , in my previous post I refer I have replaced the fan temperature switch because when I have connected the computer to the ECU I read the temperature arround to 93C and the fan not working , usually fan activate at 80C (that is the value in the sensor switch) but if at 93C I continue with this “problem” in value readed by lambda , it means , for this problem he is not occurring because the engine have (is working with) a low temperature.
 
I understand

your point of view , in my previous post I refer I have replaced the fan temperature switch because when I have connected the computer to the ECU I read the temperature arround to 93C and the fan not working , usually fan activate at 80C (that is the value in the sensor switch) but if at 93C I continue with this “problem” in value readed by lambda , it means , for this problem he is not occurring because the engine have (is working with) a low temperature.
Hi , you know there is a problem with the cooling system.
It would be very sensible to fix the cooling system so engine consistently runs at correct operating temperature in order to help diagnose emmision problem.

Open loop ecu not using signal from o2 sensor to adjust fuel mixture.

Closed loop ecu is using signal from o2 sensor to adjust fuel mixture.

Probably explains value of 1 when in open loop but does not mean mixture is correct.

Any extra air entering exhaust manifold or exhaust will affect o2 sensor causing too much fuel.

Best wishes
 
For now I only have some answers , I don’t have any values HC,CO or O2 , at inspection they only said have to much emissions , last year I lost 4 times and at last time i have the help from the inspector (I believe he help-me).

In February I have the anual inspection , and I know something is wrong because the lamba correction the value is arround 72 and must be 1 because I have measured in other same model car.
I have readed your last post and I have changed the coils but same result.
Three day ago I have replaced the switch fan sensor.
The temperature (blue sensor) is working because using IAW software I could measure the temperature.
In this car I have previously replaced all injector body , replaced ECU , replaced Lambda (removed from another working car) replaced the canister and respective valve , replaced the MAP sensor , and same problem.
Today based in your last message I do the mesure and apparently the conclusion is , with the motor cold , I start engine and the lambda shows open , and when temperature is arround 45C lambda shows close , could be coincidence because I have this test only one time , but , during the period the lambda is open , the lambda correction value is the desired , the 1. Tomorrow with engine cold I repeat again this procedure to determine if was coincidence or not.
One last procedure I have done based one factory manual is the readaptation modules , I have disconnected the blue temperature sensor, MAP sensor and trotle potentiometer in injection body and start running (have done 2km) when arrived , disconnect the battery and past 5 minutes reconnect itens previously disconnected , reconnect battery and put motor working , when hot the fan arm , i have done 3/4km km. But this don’t solve my problem.
I fact i don’t know more what to do. The strange is the car works fine , apparently there is no problem. Start well , run well.
About sparks color , if i run the color is normal , but if only put motor working for a long period with moisture rich probably the sparks goes black.
This car I think don’t have the thermostat.
If I understand you, you are saying you think the thermostat has the inside removed?? So its running coolant through the rad constantly?? This is probably your issue if thats true. Cars probably not hot enough when it gets tested..
I've seen gutted and stuck open stats on these engines in the past and you find when moving along the engine temp drops lower than normal operating temp and at idle it takes forever to get it up to proper temp.
I understand

your point of view , in my previous post I refer I have replaced the fan temperature switch because when I have connected the computer to the ECU I read the temperature arround to 93C and the fan not working , usually fan activate at 80C (that is the value in the sensor switch) but if at 93C I continue with this “problem” in value readed by lambda , it means , for this problem he is not occurring because the engine have (is working with) a low temperature.
i'm not sure thats right tbh, from memory the fan shoudl kick in at 97 and stop at 92.. Which brings us back to the stat issue...

I think i'm with Jack at this point, you need to sort the cooling system and be sure its running at the right temperatures. Put a new genuine thermostat in, put the fan switch back to normal one. And at that point I'd just take it for its test in Feb and be sure to ask them to do you a print out of the emissions even if it passes. But if its been running too cool its probably running too rich - this would make it fail even with a known good CAT on it. But if yours has been running rich for quite a while it very well may have killed the CAT.
 
Hi , you know there is a problem with the cooling system.
It would be very sensible to fix the cooling system so engine consistently runs at correct operating temperature in order to help diagnose emmision problem.

Open loop ecu not using signal from o2 sensor to adjust fuel mixture.

Closed loop ecu is using signal from o2 sensor to adjust fuel mixture.

Probably explains value of 1 when in open loop but does not mean mixture is correct.

Any extra air entering exhaust manifold or exhaust will affect o2 sensor causing too much fuel.

Best wishes
With your explanation now I understand better how it works , and this occur a question , in open loop the value is 1 (the value desired) , my question is , this is a value read in real time , or in cold mode engine the ECU have a pre defined value (fuel+air) ignoring the lambda values readed.

In my previous post I said I think probably the engine don’t have thermostat but I am not completely sure , next days I will check that.

I have talked with some mechanics , we have changed opinions , but they don’t know the exact problem , what they have suggested is previously changed , they sugest put a new catalytic and a new lambda , but is mechanics without equipments to mesure the emissions , they comment based the general .
Using multimeter I have checked the lambda and aparently ok , anyway I have changed with another from a working car , catalytic replaced too and problem is same.
I think next step is removing the admission collector to check very well if something is wrong.
When I buy this car 4 years ago , the car was parked 6 years without working. Since first inspection I have problems with emissions.
 
If I understand you, you are saying you think the thermostat has the inside removed?? So its running coolant through the rad constantly?? This is probably your issue if thats true. Cars probably not hot enough when it gets tested..
I've seen gutted and stuck open stats on these engines in the past and you find when moving along the engine temp drops lower than normal operating temp and at idle it takes forever to get it up to proper temp.

i'm not sure thats right tbh, from memory the fan shoudl kick in at 97 and stop at 92.. Which brings us back to the stat issue...

I think i'm with Jack at this point, you need to sort the cooling system and be sure its running at the right temperatures. Put a new genuine thermostat in, put the fan switch back to normal one. And at that point I'd just take it for its test in Feb and be sure to ask them to do you a print out of the emissions even if it passes. But if its been running too cool its probably running too rich - this would make it fail even with a known good CAT on it. But if yours has been running rich for quite a while it very well may have killed the CAT.
I will verify if the thermostat is there or not.
This is not my first punto 55 1.1 and normally the temperature fan switch is around 80C , in cold countries the temperature is more hi.
I live in Madeira Island and in summer with hi temperatures could put the motor in “danger” usually we use 80C , in my previous car the sensor is 80C without any problem with car or in inspection (MOT).
 
With your explanation now I understand better how it works , and this occur a question , in open loop the value is 1 (the value desired) , my question is , this is a value read in real time , or in cold mode engine the ECU have a pre defined value (fuel+air) ignoring the lambda values readed.
in open loop the sensor isnt affecting anything and yes the ecu is just using set pre-programmed values while the car warms up.. but once it goes closed loop the ecu is using the lambda signal to adjust the fueling - i dont believe it adjusts ignition timing at all, only fuelling. But part of its fuelling calculations it also take temperature into account - thus if the cars not at full operating temp its going to be running richer than if it were, enough to fail an emissions test in my experience.
 
in open loop the sensor isnt affecting anything and yes the ecu is just using set pre-programmed values while the car warms up.. but once it goes closed loop the ecu is using the lambda signal to adjust the fueling - i dont believe it adjusts ignition timing at all, only fuelling. But part of its fuelling calculations it also take temperature into account - thus if the cars not at full operating temp its going to be running richer than if it were, enough to fail an emissions test in my experience.
Correct, I don't think it adjusts timing, just mixture
 
in open loop the sensor isnt affecting anything and yes the ecu is just using set pre-programmed values while the car warms up.. but once it goes closed loop the ecu is using the lambda signal to adjust the fueling - i dont believe it adjusts ignition timing at all, only fuelling. But part of its fuelling calculations it also take temperature into account - thus if the cars not at full operating temp its going to be running richer than if it were, enough to fail an emissions test in my experience.

Now have removed the thermostat and in fact there is nothing inside , he is working direct . With new thermostat the fan is working when temperature is arround 93C , but aparently not diference in lambda readed Values.

Tomorow i will try to do another test , if in fact the mixture is too rich , i will disconnect the trotle potentiometer in admition/injection body to see if when i press in pedal trotle , more air entering at admition circuit (but fuel is same because potentiometer is disconected) to see if i find the stoichiometric mixture.
 
Now have removed the thermostat and in fact there is nothing inside , he is working direct . With new thermostat the fan is working when temperature is arround 93C , but aparently not diference in lambda readed Values.

Tomorow i will try to do another test , if in fact the mixture is too rich , i will disconnect the trotle potentiometer in admition/injection body to see if when i press in pedal trotle , more air entering at admition circuit (but fuel is same because potentiometer is disconected) to see if i find the stoichiometric mixture.
Great you have sorted new thermostat.
I am not familiar with IAW software
Could lambda correction in iaw = long term fuel trim.
Using iaw can you read lambda sensor voltage ? When engine hot and closed loop operation the lambda sensor voltage should alternate between a low voltage of around 0.2 volts to a high voltage of around 0.9 volts .
Did you get exactly the correct replacement lambda sensor?
 
Tomorow i will try to do another test , if in fact the mixture is too rich , i will disconnect the trotle potentiometer in admition/injection body to see if when i press in pedal trotle , more air entering at admition circuit (but fuel is same because potentiometer is disconected) to see if i find the stoichiometric mixture.
That won't work because the throttle potentiometer is only part of the system the map sensor is involved.
Are there any leaks in the exhaust manifold ? Exhaust front pipe?
 
Great you have sorted new thermostat.
I am not familiar with IAW software
Could lambda correction in iaw = long term fuel trim.
Using iaw can you read lambda sensor voltage ? When engine hot and closed loop operation the lambda sensor voltage should alternate between a low voltage of around 0.2 volts to a high voltage of around 0.9 volts .
Did you get exactly the correct replacement lambda sensor?
might onto something here, its only a narrowband sensor so it can't possibly be tell the ecu how lean/rich the mixture is, it can only flip between rich and lean so i think this figure its spitting out is probably misleading you to think its running really rich when its not.. Which kinda leads me back to getting a printout from the test centre off the gas analyser telling you want all the actual levels of different gases out the tailpipe are.
I'm inclined to think it might be okay now, and if its not it'll be a leak in the exhaust or intake or the CAT is now weak from the engine running too cold and the ecu enriching the mixture as a result for a prolonged period.
From what little I've read on this topic, the lambda signal is a useful diagnostic tool but not on its own. For one, as i previously mentioned its a narrowband so doesn't tell you how rich/lean it is and secondly its an O2 sensor, doesnt tell you the levels of the other gases which you need to make any concrete diagnosis.
 
I have done a video, I don’t know if I could post but , there is the link , in video excuse my bad English , sometimes I don’t have technical words to apply .
Usually I use the car for short distances 2/3km to go and more 2/3km to return.
In last part of the video i show something like water in exhaust tube , is the first time I see this , probably is the first time I look with more attention to exhaust tube.
I don’t know if someone have the same car model and could compare.
I accepting more suggestions.
 
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