FSI failed on emissions

Andrew said:
The mystery of 3750 - 4550 rpm fast idle test surfaces. Look at page 25 in the Annex.

Andy
Click to expand...
Well spotted Andy.
That explains it (fast idle 3750 - 4000), then, MoT man is, technically, correct, but not many testers go that deep, maybe, luckily perhaps.
I can only guess that the analyser kit he's using has a look up table, where he enters the vehicle\engine type, and gets the appropriate Min and Max emissions.

A2 Petrol Emissions Spec.jpg


So, sadly @dances-with-pies still has a problem, but he'd probably be OK at most other MoT Stations.
Good reason to go to the same MoT Test Station every year.

Previous suggestions, cataclean etc still valid ...

I've edited my previous posts.

It seems that not many MoT testers go this deep, but it's there if they do.
Mac.
 
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@A2Steve
Could you ask ProBoost to comment on whether the ProBoost map allows for these requirements?
Because it's an A2 BAD, it could be tested against the requirements above, especially the lower idle speed (600 - 820 rpm), and higher fast idle speed (3,800 - 4,500).
Mac.
 
My fsi caused unknown problems similar to what you are experiencing:

Mechanic found fuel filter had not been changed for 7 years and as a consequence, the filter had disintegrated and fouled up the fuel rail system that had to be cleaned overhauled.
This did not fully clear all of the problems therefore, we changed the fuel pump.

Now car runs like ‘Meatloaf’😂
 
Three points.

1. 3750 - 4550 rpm used does not quite match the figures in the Annex, but same ballpark.

2. The test rpm cannot be that important. If you look at my emissions report above the tester did not even check it!!!! Suspect experienced tester's ear says engine sounds busy enough that will do..

3. These explanatory guides are so difficult to read with so many ifs and buts and conditions, need to read five times before it starts to make sense but I have come out of page 4 with a gist of the higher figures only come into play when the the 'normal' (2500 - 300 rpm) emission test is failed AND A SECOND EXTENDED TEST IS NEEDED, I quote

".......... then the analyser will automatically schedule an extended emissions test using the values quoted in Table 1 or Table 2 and the listings in the Annex in this booklet"

Maybe I have got it wrong.

Andy
 
Andrew said:
Three points.

1. 3750 - 4550 rpm used does not quite match the figures in the Annex, but same ballpark.

2. The test rpm cannot be that important. If you look at my emissions report above the tester did not even check it!!!! Suspect experienced tester's ear says engine sounds busy enough that will do..

3. These explanatory guides are so difficult to read with so many ifs and buts and conditions, need to read five times before it starts to make sense but I have come out of page 4 with a gist of the higher figures only come into play when the the 'normal' (2500 - 300 rpm) emission test is failed AND A SECOND EXTENDED TEST IS NEEDED, I quote

".......... then the analyser will automatically schedule an extended emissions test using the values quoted in Table 1 or Table 2 and the listings in the Annex in this booklet"

Maybe I have got it wrong.

Andy
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We need someone with quasi legal knowledge to help us understand the meaning of the "Sir Humphrey'esque" language I think.
Mac. Any volunteers?
 
We need our own resident MOT tester to clear this one up. Or is this a case of let sleeping dogs lie as some testers are not using this high rpm figure, unless you want your engine revved that high! I can hear all those fragile plastic coolant components pleading.
 
audifan said:
We need our own resident MOT tester to clear this one up. Or is this a case of let sleeping dogs lie as some testers are not using this high rpm figure, unless you want your engine revved that high! I can hear all those fragile plastic coolant components pleading.
Click to expand...
Zzzzzzzzzzzz
Rover 🐶
 
Andrew said:
Three points.

1. 3750 - 4550 rpm used does not quite match the figures in the Annex, but same ballpark.

2. The test rpm cannot be that important. If you look at my emissions report above the tester did not even check it!!!! Suspect experienced tester's ear says engine sounds busy enough that will do..

3. These explanatory guides are so difficult to read with so many ifs and buts and conditions, need to read five times before it starts to make sense but I have come out of page 4 with a gist of the higher figures only come into play when the the 'normal' (2500 - 300 rpm) emission test is failed AND A SECOND EXTENDED TEST IS NEEDED, I quote

".......... then the analyser will automatically schedule an extended emissions test using the values quoted in Table 1 or Table 2 and the listings in the Annex in this booklet"

Maybe I have got it wrong.

Andy
Click to expand...
Andy,
I'm sure you have read it correctly, and only if the vehicle fails the "Basic Emissions Test" will the tester be required to progress to the "Extended Emissions Test"
So, we're back to the conclusion that @dances-with-pies MoT tester is either not testing his A2 correctly, in applying the Advanced Emissions Test before the Basic Emissions Test, or the car has Failed the Basic Emissions Test, and the tester is correctly moving on to the Advanced version.
@dances-with-pies should ask his tester why the advanced test was run. If it was because it failed the basic version, then he needs the results from that failed basic test, as that's what needs fixing.
Alternatively, if the tester started with the advanced test, then a mistake has been made.

Know what the fault is before you try to fix it.

Mac.
 
My household has four daily use cars which all get MOT'd at the same garage.
The A2 has passed there before but only just. I'll find the previous results when i get home.
The last two emission tests took around 45 minutes each with regular head shaking in my direction.
So far the garage have refused to charge me for the tests! They genuinely want to see it pass.
 
dances-with-pies said:
My household has four daily use cars which all get MOT'd at the same garage.
The A2 has passed there before but only just. I'll find the previous results when i get home.
The last two emission tests took around 45 minutes each with regular head shaking in my direction.
So far the garage have refused to charge me for the tests! They genuinely want to see it pass.
Click to expand...
Did you ask them why they did the advanced emissions test, at higher idle speeds etc?
My, and others, reading of the guide, says basic emissions test first, but if the car fails the basic test, and only if it fails, is the advanced test run. Your fail reports show the advanced test was run, so we're wondering why?
Mac.
 
Your car passes CO at natural idle.
The same test should be reoeated at between 2500 - 3000 rpm.
If emissions are in spec at natural and fast idle, the car has passed the emissions test.

Your tester though, runs the fast idle at a much higher rpm, (around 4,000 rpm), which will, I think, give the higher emissions which the report shows.
It is possible that if your tester did the fast idle at the rpm specified for the basic emissions test, between 2,500 and 3,000 rpm, it would pass.
Sounds like your tester is a genuine guy, so will understand the query.
Mac.
 
This is the emission test results from the MOT that came with the car.

Emissions 2018 pass.jpg


CO was comfortably within limits.

When I first took it for an MOT it struggled because I got two test sheets.

Emissions 2019 fail.jpg


The CO was too high both times so he tried again and eventually got it to pass.

Emissions 2019 pass.jpg


The following year it passed OK but it clearly struggled.


Emissions 2020 pass.jpg


My last two attempts had massively high CO readings.
I had fixed the air leak by replacing the N80 valve. Maybe the problem was always there but the air leak actually helped!?

I don't know what to try next.
I don't want to remove the injectors when it runs smoothly and doesn't misfire but I can't believe that a new cat would lower such high values.
 
Have you done the usual temperature test of the catalytic converter with an IR thermometer (youtube it). Basically there should be a prominent temperature difference between the front and the back of the catalytic converter. The lambda sensor, the NOX sensor (not cheap) and the exhaust gas temperature sensors are all service items and should be replaced and all play a critical role for emissions.

EDIT: I just saw that you replaced the lambda sensor but was it an OEM part? Also using anything else other than graphite grease on the threads can damage the sensing element when it starts to burn off.
 
Well, a similar thing has happened to my car previously.
Before the MOT I was always taking the car for a spin at high revs to "clean" the engine. 3 years in row I was having high emissions in the MOT.
The gas I have used is a premium 100 octane gas ( 100 tho ... instead of the 98)

4th year i have just filled the tank with regular 95 and few days later i remembered that my MOT is going to expire ...I just took the car with a cold engine to the MOT and surprise :) no emissions, all perfectly.

Perhaps the car may not be able to burn the 100 octane gas and leaves residues on the exhaust.

I have only driven the car for few hundred kms past 2 years and it had a lot mechanical problems, im reviving it now so I'm quite curious how my emissions will be.
I'll fill the tank with a premium 98 before going. Planning on changing the G295 Nox sensor as well, I've had some errrors on it but my gas is over 1 year old in the car so untill i flash the system and fill it with fresh gas I'm not going to make the decision whether to or not change it.
 
dances-with-pies said:
I can't believe that a new cat would lower such high values.
Click to expand...

It might well, since that is what cats do.

To me, it sounds like you need expert professional help. Gary at B&F Autos in Hounslow http://www.bfautos.co.uk/ is your closest such expert, and I'd be inclined to give him a call.

WOM in Uttoxeter https://womautomotive.co.uk/ is the other significant option.

It's really difficult sorting out emissions on any car once your MOT has expired, and all the more so with an FSI. If you decide to go with professional assistance, speak to whoever you choose, get a clear commitment to getting the car through the MOT, and then ask them to book you in for the work and the test. Providing you're booked in for an MOT, you can drive the car there quite legally.
 
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