S4 Breather hoses/ catch can/ PCV valve

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hooblah

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Long winded but I'm attempting to install a BMC CDA air filter/induction kit and was wondering what I have to do with the breather that goes on the side of the air box?
I will be removing the aux rad and fitting a flexible duct to route air to the filter.

Secondly, I was doing a bit of reading and found that replacing the pcv valve can cure excessive oil consumption. One of my exhaust tips goes black quite quickly.

Thirdly, is it possible to vent crank case direct to atmosphere or do I need to use an oil catch can?

Thanks guys.
 
Is it the carbon fibre cylinder style one?
 
Honestly matey I wouldn't bother, those intakes are horrendous for choking cars, you'd be better off keeping the standard setup and dropping a aftermarket panel filter in.
 
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You mean the CDA specifically or induction kits in general ?
 
The CDA, neither the 1.8t 20v or tfsi boys will touch them, depending on the setup they can be more restrictive than the oem setup.
 
Oh right. Is that due to the filter? Because the one I have my eye on has 3" inlet and outlets, which is the same diameter as the factory intake pipe so I can't see that being a restriction?
 
Yes it's how small the filter is inside that's the issue.
 
Oh right, well thanks for that. My next step is to then make my own cold air intake with a large filter and silicone pipes.

Is anyone able to explain what I need to do with the breather that goes into the side of the air box, or if I can replace the whole lot with a catch can or open breathers?
 
So you have a pictures of the breather? On the early 1.8t 20v's they used to have a breather going into the airbox for the secondary air pump. May be similar to that.
 
Dani I think you're right. After viewing the etka diagrams I believe it to be for the air injection pump. Ok so problem solved.

After many hours of research I have come to the conclusion the standard air box is the best option, but with a duct to the fog light.
Why? Because after viewing another thread based on a B7 rs4 it looks like it won't be prone to heatsoak as compared to other enclosed filters. The user had removed the aux rad and put a duct to his GruppeM carbon induction kit. He had insulated it from heat quite well, including making heat shields and using gold reflective tape. Unfortunately after all the hard work it turned out his inlet temps were still higher than with the standard air box.

http://audisrs.com/archive/heatshield-and-gruppem-cooling__o_t__t_26175.html
 
Well I've kept the standard airbox, dropped a pipercross panel filter in and used gold reflective tape in the exsisting heat shield, I also removed the internal sound deadening and cage inside the airbox and the car seems to live it, even in the hot weather we briefly had.
 
What about heat wrapping your manifolds and turbo

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I think youre in the wrong section mate. Firstly there is no turbo, secondly you're having a bubble if you think I'm pulling my engine to wrap the manifolds.
 
Read the other thread now. If you wrapped the manifolds from below you could get enough room on the ramps

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So this weekend amongst other things I deleted the aux rad and changed the pcv valve.
Started the car up and left it idling, after a few seconds I thought oh **** I need to add some coolant. Can't have been idling for more than 5 mins until I topped it up. There was still water I the system anyway.

Ok so after a few mins the car started smoking heavily from the n/s exhaust pipe (thick white smoke). The other one was fine. I thought meh, it's probably just oil in the breather system. So I took it out for a hard drive for 10-15 mins. I got home and was suffering from.brake fade. The street was filling with smoke from my brakes. But no smoke.
A minute or two later it starts smoking again. N/s exhaust pipe. I have the factory exhaust.

So seeing as it's only smoking from one side, did I blow the head gasket because I didn't top up the coolant fully before I started the engine? If this isn't the case what else could be the problem? I didn't touch anything else on the engine and now I'm shitting bricks!
 
Last edited:
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It is possible to but highly unlikely you have blown the head gasket. To check take out the spark plugs and you will have a clean piston head

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Ok solved. Thanks for the input.
 
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What was it in the end . ?

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Lol fair enough

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