Strange idle connected exhaust vibration

[Acidburn]

Stick with it lou, there can't be much else thats un changed on the car. If I can get down sometime soon i'll have a look.

[220bhp]

Stick with it lou, there can't be much else thats un changed on the car. If I can get down sometime soon i'll have a look.

Any help would be much appreciated.Apart from that its always good to seee you mate

[newsh]

If you don't change the injectors it will run very rich. And if you change back to 3B ECU and injectors you'll need to have a 3B FPR, I imagine it will be on a 7A item at the mo..

How about the Lambda?

[220bhp]

Alred, came to help me today ,and we managed to do quite a lot of testing. Which resulted in the car running better than it has todate.
We found a possible short on the round connector on the lamda,which had throne a code.
Also we found that the TPS was giving a low reading at WOT,so we changed that for one which did check out.there are no boost leaks,but using my trusted tounge test on all the vac lines the only one that did not pass was the pink line to the diflock,this will not hold vacumme.
Read the codes again after clearing and trying the car, and the only fault that returns is 00533,which would not clear with the engine running.
And as I have a new ISV on order,should solve the problem,but only time will tell,fingers crossed.

Lou

[newsh]

Have a look under the back seat to see if the diff lock line is disconnected.

In the pic the one way valve should be plugged into the rubber T piece.

Its also possible that the one-way valve is stuck open.

[220bhp]

Thanks John

[220bhp]

Managed to change the ISV today,for a new one.After all the efforts put in by Alred last Sunday,we both thought it would be the culpret,but sadly not.
After fitting the new one I cleared the codes,buy dissconecting the battery,because my new vagcom cable wont work,the car still is not right.
Firstly the revs oscilate when it is at around 1500 revs. secondly the throotle response is very poor. Thirdly the the boost has now dropped to just over 1bar.And finaly the exhaust drone has returned, although not quite as bad.
I have checked that the one way valve under the back seat is connected, but I still have to check if it is working,if anyone knows how to do that please let me know.
Asfar as a vaccume leak is concern,and I understand this could cause the problem,I have tested and replaced all the hoses,and the only one that will not hold vaccume is this pink hose to the valve.
The only other thing is the n75,which is vented to air ,on MRC reccomendation,but I hear that quite a few people run like this.
I have to say my long love affair with Audi is in danger of coming to an end,as all three of my cars are giving me grief at the moment.
S6 has been a pain to get through the Mot for the first time ever.Having done realy difficult jobs,like removing the stearing rack,rear shocks ,and handbrake cables,the Abs is causing problems,and there is a fluid leak coming from somewhere.
My wifes v6 cabby is running like a bag of ****,with the old problem of lumpy running and stalling when you start it.
So as you can see things are not great in the fleet at the moment,plus I have so much work on at the moment its hard to find the time,or the enthusiasm,to do much.
However, if anyone has any ideas as to what might be the problem with the S2,I would be greatful.

Many thanks lou

[twoqu]

Lou,

Just how exactly is the N75 plumbed in?

[220bhp]

Lou,

Just how exactly is the N75 plumbed in?

Robin the n75 was removed from its stock location entry to the maf hose,and the hole in the maf hose was pluged.the hose from the wastegate was shortened and the new location is up near the waste gate.
This was Mineah,s idea after talking to another tuner in germany,because he was having problems mapping my car.
The car was mapped like this on the final run.
PRJ has since suggested that this will pull in unmetered air,but MRC disagree.
Dont know what to think myself.

[prj]

PRJ has since suggested that this will pull in unmetered air,but MRC disagree.
Dont know what to think myself.

They can disagree all they want - physics are physics...
You can argue about how much difference this makes, but you can't argue about the fact that it is occurring. This will always happen on idle for example.
When the turbocharger is providing basically no pressure, then it is easier for air to go through the N75 than go through the turbo and through the filter.

[220bhp]

They can disagree all they want - physics are physics...
You can argue about how much difference this makes, but you can't argue about the fact that it is occurring. This will always happen on idle for example.
When the turbocharger is providing basically no pressure, then it is easier for air to go through the N75 than go through the turbo and through the filter.

Many thanks for your advise.It is my intention to put it back to stock location,but at this moment in time it is not possible, as the hose to the waste gate is now to short,and I beleave this is a heavy duty hose,so I will have to get a new one.
Do you have any idea why the car runs well coming up to tempreture and then bad when its hot.

[prj]

Have you fitted stock injectors and stock ECU?

[220bhp]

I did replace the ecu,with a stock one,and tried it without changing the injectors and the fpr,
just to se how it ran , the poor idel and running where just the same ,so I never tried it with the injectors and the fpr. Perhaps this was a mistake.

[prj]

I did replace the ecu,with a stock one,and tried it without changing the injectors and the fpr,
just to se how it ran , the poor idel and running where just the same ,so I never tried it with the injectors and the fpr. Perhaps this was a mistake.

Yes, this was a mistake.

[twoqu]

Right, so the leg thats usually in the MAF hose is open to the atmosphere?
If so, when the N75 is powered up it will as I understand it allow the turbo to suck unmetered air through the turbo as Dmitri has suggested. Not sure I understand why it was done like that.
No need to reconnect it, just put your finger over the end and see if the idle improves!