Oil cap vacuum

[Garry A4]

Hi there could anybody help me with this issue
I own a A4 2.0l avant Quattro s line and i've got problems with the revs fluctuwating up and down when warm
and when engine running if you take the oil cap off there is suction ...
any ideas please

 

[SDHA4SLine]

Now I've been taking advice on another thread about a possible blocked crank case breather from a4rob and desertstorm. Maybe this is your cause hopefully one of those two can chip in (they both know their stuff).

All I know is I went to audi and tech said if breather is blocked a sign of this is the filler cap is hard to remove as it will be sucked down.

Is yours tdi or tfsi?

 

[Giosabcsl]

Once I know if this is petrol or diesel I can give my input as if its petrol I wrote a looooong thread about it on the forums which I can link to you.

Also besides stating if its petrol or diesel could you state the rev fluctuation is this during idle or when changing gear if you could add some more specifics.

And welcome to the forum btw

 

[Charlie Farley]

could you drop me a link to it , i'd like to have a read through it for future ref.

 

[Giosabcsl]

Sure buddy let me just grab it for you.

Here you go : http://www.audi-sport.net/xf/threads/pcv-help.190417/

A bit of a read. Looking back now I thought it was longer maybe I typed more in another post but that gives you the general idea.

And further down the post there is more info, thou I haven't re read it myself but if you need any further clarifications just feel free to pm me or continue posting below

 

[Charlie Farley]

thanks for that, i do try to absorb as much info as possible on matters automotive etc , never hurts to have enough data on these sort of things.
thanks

 

[Giosabcsl]

I agree. Thou you always have the option or choice should I say of asking Thou dont ask me ill make your ears bleed lol

 

[Charlie Farley]

there is a newer revision now of the pcv valve , it's 06F 129 101 R and its the newest available to date , picked up one last week for my other BUL project, £38.00 from audi inc vat. they had quite a few in stock which means its a commonly requested part then.

 

[Giosabcsl]

It all depends which one you had on previously and also the colour of your valve cover.

Thou you are correct in what you have said R is the latest for your vehicle but for mine its P.

And bare in mind that post was 2 years ago.

Hence as explained you can just slap it on and hope for the best as you can cause all sorts of issue especially with the check valve in the breather pipes.

 

[Charlie Farley]

the pcv valve on my avant and project engine both have the same as yours rev c and with the black cover, i asked dealer for a "p" rev but only the newer "R" was availble for my applications , so just went with that, straight replacement .

 

[SDHA4SLine]

Oh balls is my advice bull?

 

[Giosabcsl]

the pcv valve on my avant and project engine both have the same as yours rev c and with the black cover, i asked dealer for a "p" rev but only the newer "R" was availble for my applications , so just went with that, straight replacement .

My cover is silver not black . And I hear what you saying but remember all your dealer is doing is telling you what his computer is telling him. Ask him what a DTM is or a I dunno scuttle tray he will be like what?? what's a dtm. Unless you have one of the fortunate ones. I have tried numerous dealers I even got told the one day "sorry we dont sell the race parts for our race cars" he thought I meant the DTM race vehicle...to say the least was a priceless moment.

But as started R is for you application.

 

[Giosabcsl]

Oh balls is my advice bull?

Your info was partially correct as when you remove it there is a lot of resistance then the PCV is the issue. But that said there should be some resistance as you are breaking a vacuum. And our vehicles work on a vacuum if that makes sense. So call it a gentle suction.

 

[SDHA4SLine]

Oh that's good then, I'm genuinely trying to be a helpful member rather than just taking all the time. Mines a dirty diesel if that makes a difference.

 

[Giosabcsl]

Be gone traitor lol... No im kidding. I understand.

Well that is what we all are here for to help ea other out and its slightly different set up on a diesel sadly.

 

[Charlie Farley]

yep, fully understand where you're coming from, my original method was to just ask him for the pcv by part number i had tracked down,which , he came back with the info requested , but to be double sure i then asked him to cross ref it with the vin number aswell as both engines are bul's with black covers, he went off for a while and came back with the exact same part number, so i think in this case i was lucky to get the correct part but i can understand your concerns when trying to replace yours, must have been total pain in the backside to get it sorted via the spares dept.
at least you got it sorted in the end.

 

[SDHA4SLine]

Be gone traitor lol... No im kidding. I understand.

Well that is what we all are here for to help ea other out and its slightly different set up on a diesel sadly.

Too late for me I'm done for, leave me, go ahead without me

 

[Giosabcsl]

I did indeed yes. Sadly people in this world don't realise that there are other human beings with more knowledge than them when it comes to certain things and Audi seem to think they are an inferior breed even when you tell them something which is blank in there face they still tell you the sky is green.

None the less I am taking over GarryA4 forum post. Hopefully all our cross chat will help him with his issue.

 

[Charlie Farley]

hopefully all this info will help put him on the road to recovery now.

 

[Garry A4]

Once I know if this is petrol or diesel I can give my input as if its petrol I wrote a looooong thread about it on the forums which I can link to you.

Also besides stating if its petrol or diesel could you state the rev fluctuation is this during idle or when changing gear if you could add some more specifics.

And welcome to the forum btw

 

[Garry A4]

Hi guys and thanks for the welcome It is petrol and it flucs when idle only when engine is warm and I've noticed when I'm changing gear whilst driving a long time
Once again thanks

 

[SDHA4SLine]

Now I've been taking advice on another thread about a possible blocked crank case breather from a4rob and desertstorm. Maybe this is your cause hopefully one of those two can chip in (they both know their stuff).

All I know is I went to audi and tech said if breather is blocked a sign of this is the filler cap is hard to remove as it will be sucked down.

Is yours tdi or tfsi?

Sorry just noticed was taking advice from ajax1976 rather than a4rob. Just thought I should correct that