FSI erratic/uneven running

Rest of images

11sin.JPG

12sin.JPG


I leave some important channel to capture image?

Thanks very much.
 
Was your MAF sensor disconnected when you grabbed those screen shots?

Your MAF value is too low and your intake temperature is also to low, but easily explained by the MAF being disconnected.

If it was disconnected, reconnect, take the car for a short run and then allow to idle. Take a snapshot of Group 032.

Are you running 98 RON unleaded?

Nick
 
Hi Nick, yes the MAF is disconnected. Repeat the captures of images with the connected MAF in having some free time.

Thank you very much for your help.

A greeting.
 
what values should the lTFT and the other STFT give?

THANKS VERY MUCH!
 
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looking at the pc I saw that I had not erased the images I made with the MAF sensor connected. The only thing that are not all channels because I ran out of battery.

Here they go:

1con.JPG

2con.JPG

3con.JPG

4con.JPG

5con.JPG

6con.JPG

7con.JPG

8con.JPG

Any idea why the car is better without the MAF, if the MAF is not broken and works well?

Thank you
 
In the Spanish forum that I am '' areavag '' can not help me well because there is only one person who has an a2 1.6 fsi, which is the one that I talk about this forum. That is why I ask so many questions, I want to help all that I can to my mechanic to find the problem.

Does anyone know which channel the MAP sensor is on?

Why with my 12.12 vagcom I can not see the value of the injectors or the instantaneous consumption? I'm missing a label or the one I have is not current?

Thank you
 
Without the MAF sensor the car runs in a safe mode in which it makes the mixture rich to avoid detonation. With it connected the engine adjusts the mixture to be as lean as possible without causing detonation. Interestingly, you were showing misfires without the MAF and none with.

If you don't have any error codes then you could try a good injector cleaner additive, some people have had success with this. The A2 FSI should also be run on 98 RON octane fuel, the difference is noticeable.

LTFT should ideally be <8%, in a perfect world it would be 0 but with the MAF disconnected it will be high as its assuming a rich mixture on purpose.

Unsure of VCDS issues.

Nick
 
I understand you make a richer gas mixture when you're in safe mode? Get more fuel with the MAF disconnected? It is that I consume the same with the connected MAF without it, and I think it should be the other way around, right? Does the connected MAF adjust the mix automatically as poorly as it can?

Do not mention it in the initial post but I already throw a boat of clean injectors and 98 octane gasoline and did nothing.

Right now I do not get any mistake the vagcom.

thank you very much

Andrés
 
The MAF works in connection with a number of sensors to determine the correct mixture, in theory you should use less fuel in "homogenous" mode than in "safe" but that is assuming all sensors are giving the correct information.

The FSI is difficult to diagnose with many suffering the same symptoms but with very different causes. Without a fault code it's difficult to point you in any direction, but always start with the basics, for me that's intake hoses and pipes.

Nick
 
.......

Why with my 12.12 vagcom I can not see the value of the injectors or the instantaneous consumption? I'm missing a label or the one I have is not current?

Thank you

Current Ross-Tech download of VCDS is Release 17.8 - Andy
 
Crikey, how long has this topic been going .
I joined in a while back as I had the same symptoms as the original post.
So far I have fixed a fuel leak, replaced both lambda sensors among several other fixes and none have really changed anything. ( I thought I had fixed the fault but must of imagined or wished it)
Anyway after changing the lambda sensors, due to out of range readings, and not making a difference I thought to look at what would make the lambda go out of range. First thing that spring to mind was the egr valve being irratic sending irratic gulps of exhaust gas through, so I simply blocked off the valve and hey presto it runs lovely now.
Don't know if this helps anyone but I had to tell someone......
 
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Hello again, after being very busy this month at work and at home I can say that after being the car a week in the mechanic, they have not found the fault. They think it may be from some air inlet or vacuum pressure failure.

Harring, Did you cancel the EGR valve with a sheet and have you fixed all the problem you had?

Greetings from Spain.
 
Crikey, how long has this topic been going .
I joined in a while back as I had the same symptoms as the original post.
So far I have fixed a fuel leak, replaced both lambda sensors among several other fixes and none have really changed anything. ( I thought I had fixed the fault but must of imagined or wished it)
Anyway after changing the lambda sensors, due to out of range readings, and not making a difference I thought to look at what would make the lambda go out of range. First thing that spring to mind was the egr valve being irratic sending irratic gulps of exhaust gas through, so I simply blocked off the valve and hey presto it runs lovely now.
Don't know if this helps anyone but I had to tell someone......

Hi
You have petrol engine, 1,4 or 1,6? Doesn´t blanking EGR light up some warning light at the instrument panel...?
 
I simply used a blanking plate on the egr, I did not do anything else and it has been running fine since with no errors or warnings lights
 
This does NOT affect the emissions test as mine passed its MOT the very next day.
The only issue I have left, (which I believe is a totally different issue) is when I start the car the revs go below tickover for a second then return to normal. The car has always done this, not a new fault. It is not really an issue as does not stall and only happens on start up for a second, but I would like to sort it if I can. If I do I will post here.
 
Hi everybody how are you? I have news regarding my breakdown. Now I get 3 new mistakes that did not work before.
I do not know why they have taken so long to leave since the car has been missing for at least 2 months with those symptoms.

I have the new scan that I will hang next and reading the channels that a colleague asked me to see if the reading is correct or wrong.

IMG_1162.JPG

IMG_1166.JPG

IMG_1167.JPG

Let's see if you can help me a little so I can go to the mechanic and guide you a little.

Many Greetings from Spain.

Andy
 
Sorry, the picture number one repeated well.

IMG_1162.JPG
 

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Did this thread ever get to a conclusion. i have a 1.6FSI that is not easy to start with the engine hot. No error codes. I suspect a O2 / NOx sensor however....?
 
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