Charlie Farley's 2.0tfsi Full PCV Delete project, and why you need to do it too.

Charlie Farley

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Jun 13, 2014
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In Surreyshire
Well I thought it was about time to do a project write-up , and what better way than on that old chesnut , the PCV delete for the 2.0tfsi as fitted to the A4 B7, but will also apply to other tfsi based engine fittments in other variants.
This is long write up so you may need a cuppa & biscuits to help get through

So why bother with it one may ask , after all audi spent a lot of development time on the oem setup, well it's quite simple really, it doesn't work.
Well that's not strictly correct as it does work very well at making the engine emission friendly etc , which is good for the environment, but , it does nothing for the engine other than choke it up with carbon build up and sludge residue etc throughout the intake system and that has a detrimental effect on performance etc and does not really make for a clean and efficient combustion .

If in doubt ,check you intake manifold and inlet valves , they will be choked up with carbon, which will need cleaning of at some point, if you are a turbo engine variant pull of the bottom intercooler hoses and see what comes out......its not good frankly.

It happens to many, many engines across all makes etc , some are worse than others but Audi FSI and TFSI are certainly effected quite badly due to the direct injection method used, and its across all engine capacities inc the NA V8's , anyway there is a lot of well documented info on the web on the whole subject so that's enough of that chat.

So to my project and what I hoped to gain. As a 2.0tfsi owner I have also been plagued by the problem of excessive carbon build up in the cylinder head , lots of excessive oil residue in both my intercoolers and pipework, well the whole intake system has been effected to more or lesser degree due to the way the OEM PCV setup works, and that is on an engine that has only covered approx. 30k miles.

The time has come to put a stop to it all and clean things up now, for good .
Having spent a lot of time researching what the option were and what parts or kit's are out there it became clear very quickly that there are a fair few options on the aftermarket front but only a few for the A4 B7 varaints.

Numerous companies make part delete plate kits or just plates , some with or without a catch tank option only a few makes kits for the B7 and then they are not really full PCV delete kits as there is no such a kit , it is left to the individual to make there own , which is what I have done.

First off I'm not plugging any specific brand or company, just what I used and found to be ideal.
Having tried the dual tank setup and being very impressed with how well it deals with the issue I decided to revise the installation to a single tank setup but still covering all aspects of the PCV , also there just is not the space to run two tanks to be honest.
A lot of large bore hoses both all over the engine bay, I had to remove the air filter box to fit the second tank, and also heat on the second tank hoses was not helping with reducing heat soak either, there was a lot of extra hot air being put back into the turbo .

My project goal was to:
(1) make a more user and engine bay friendly setup that did not increase the overall temp of the gases in the pcv going to the turbo .
(2) A setup that would address both sides of the pcv problem not just the front side of things .
(3) A much more cleaner running and better performing engine .

I feel my project has succeeded in all these areas, the car idles perfectly , has no adverse running issue with the setup and the engine runs cleaner and performs better without having all those oil laden vapours etc being recirculated around the intake of the car.

I used a PCV delete kit from R-tech, you get a nice well machined PCV plate, manifold intake plug and hoses I didn't use both the hoses included which was my personal choice, only the 25mm one suited my purpose.
Next part was a Mishimoto 3-way billet oil catch tank, not a very large capacity tank but ideal based on the available spare in the B7 engine bay, and it has drain option too so emptying on a regular basis is not an issue.
A 25mm alloy self sealing hose barb

A few sundry parts such as 19mm hoses tails and some 19mm & 25mm alloy pipe, some braided hose covers that I had for my previous installation.

A turbo blanking plate , as the rtech kit supplied plate is way to small as its not intended for the K03 in the B7 so I fabricated my own.

The install :
Pretty straight forward for the most part, you'll need to remove all the oem pcv components which are the , PCV valve assembly, plastic hose link from pcv valve to intake manifold, plastic feed hose from engine crankcase to the pcv valve.

depending on your choice of entry point for the return feed back into the turbo either the whole vent pipe and replace with a blanking plate or use a modified vent pipe.

keep in mind for the install to be a full PCV delete you will need a 3-port tank or a means of joining both feeds to the tank , this only applies if you are using one catch tank to service both front and rear PCV vents.

Choose you location for the tank , you'll need 19mm OD hose for the PCV feed from the cranckcase to tank , 25mm OD hose from the rear vent on the valve cover to the tank and 25mm OD hose for the return to the turbo.
using these size hoses retains the internal bore size of the factory pipework so less chance of restriction to flow.

The plastic oem hose that was removed from the pcv feed from the crankcase will need to be used in a minor way , you'll need to carefull cut the hose on the engine end and remove the oem plug as that will be your connection means to refit the new hose.

still here , good, nearly

You will need to refit the R-tech PCV delete plate , don't over tighten it , also fit the intake pipe plug to seal the now open port left from the removal of the short plastic link hose.
At this point you should have all the parts fitted except for the connection to the turbo, I choose to blank of the oem input port on the turbo with a blanking plate and instead fitted a 25mm self sealing hose barb just above the oem entry point in the TIP pipe, this works out better due to space restrictions in the area as I am retaining the oem airfilter box.

My project uses braided hose covers as I had them and I found by routing the hoses in the way I did kept joints to a minimum and less stress on the connections at each hose end.
I used a pipe bender to fabricate the 90 degree bend in alloy pipe to pass next to the airfilter box and into the vent as the limited space does not allow for the use of conventional hose but alloy pipe has a thinner OD so this worked out well.

that's about it really, so it's goodbye excessive carbon build up, goodbye oil in my intercoolers and elsewhere for that matter, hello to cleaner air and cleaner running engine's a win, win situation really.

If you have taken all that in then good onyer, and good luck.
Some pics of the install and I will put up some other instructions if needed, but to be honest it is not that difficult , but you need a plan before you start and make sure it all fits in place before you cut bits.

You wont need those pcv bits anymore either and you wont get nasty carbon issues of a bucket full of crud from you IC's.....

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Now with that task completed it is time to remove the intake manifold and perform a full decoke of the manifold, runner flaps and inlet ports/valves , and also remove both intercoolers and pipework and give them a full degrease and flush through......

With a nice clean intake system and intercoolers and a efficient PCV delete oil catch tank setup ,new DV , R8 coilpacks and iridium spark plugs , 034 TIP & K&N panel filter and 034 sport cat with large bore down pipe , using 98 super fandango fuel will be well worth the costs and the performance gains from it added to the other upgraded parts will be noticeable without having to spend too much more cash.

Oh happy days....
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You want to forget putting a tank in the turbo side of the engine bay, it just gets to hot chap, space is not at a premium to start with and the heat in that side of the engine bay with the bonnet closed just boils the contents of the tank and the separated air is really warm , so sticking that hot air back into your turbo intake just defeats the object of having cold air drawn in, it just heats up things even more.
you need to route the pcv and the crankcase venting to one tank or two tanks on the cooler manifold side, trust me, it makes a massive difference.

Thought we should continue this discussion in this thread mate.

I've been considering blanking off the breather pipe between the crank case and turbo with these -

But not sure if this will have any adverse affects e.g. oil and carbon building up in the crank case? Or will the catch can on the PCV delete deal with that issue? I suppose oil and carbon would be better building up in the crank case than the turbo/intercoolers?
You mean like this....
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with one of these then, I just made up a couple out of some sheet material I had in the workshop, same thickness as the original section etc and used the oem sealing gasket, took me 30 mins top to make 2 plates, maybe I should make a batch run for bods at a nice cheap price, the r-tech ones are too small for B7 K03 turbo's .
You need to vent the crankcase outlet from the camcover , either to a tank if not venting to atmosphere and then return to this port , if you are blocking it then you need to go back into the intake somewhere , I went in to the silicone intake pipe just above.
Works great, the suction in the intake pipe helps to draw gases out and create a flow around the new setup, so the pcv feed gets drawn out nicely as does the crankcase and the both merge in the one tank, one return to the turbo via the intake pipe and that's it.

No issues at all thus far, all the gunk is in the tank, only clean air is going back into the intake now....
Car runs spot on, no idling issues or smoke now, even better mpg aswell , and no smells that you'd get with vent to atmosphere setup.


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Yeah that's the one.

I'm tempted to try one of the cans with a breather and vent the crankcase to atmosphere rather than taking it back to the turbo/intake. Do you know if there are any drawbacks to doing this?
why don't you want to take it back to the turbo or intake Dan, if the return is from a tank then there in no problem, there is no way of collecting all the gunk otherwise, venting to atmosphere will just let it all out somewhere else along with the smells and smoke etc, unless you have a means of collecting all the byproducts then it has to go somewhere , either out to the air or back into the engine via intake and intercoolers etc, both options kinda defeat the object of the exercise really.
I’ve just never liked the idea of recirculating any blow by, gas or vapours. I know catch cans are designed to collect most of the oil/gunk but I’m just curious if there is a set up that could remove the need to go back to the turbo or intake
fitted the drain hose and tap to the tank and routed it down and out just under the undertray, so just twist and empty....oh happy days, all the nasty stuff in the catch tank can be disposed of safetly and not being recirculated around my engine.

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So a few weeks on and time for an update on the project.
So touch wood no downsides at all, no air leaks etc, no nasty odours , but there are a few extra plus points that I wasn't really expecting.
First one is that my old sooty exhaust tips have prettywell cleared up, after a few weeks the insides of the tips have only a very light layer instead of the thick layer before, so that's brill.
next bonus is that the fuel consumption has improved quite a bit over previous consumption, especially noticeable around town when driving sensibly....
open road /motorway has allways been good anyway but I expect that's improved also, I suspect all that nice clean air / fuel mixture is burning much cleaner now.

Drain pipe setup is great and makes for such a pleasant job to empty the tank.

Next job is to decoke the head and clean out the IC's fully and then I think i'll be fully sorted.
Glad to see it all work out for you chap.

You be done a very neat install and improved upon the idea I had for it.

Out of interest though, the mishimoto can you have used 3/8 thread, what size barbed tails have you used, 1 x 19mm and 2 x 25mm or are they all 19mm as I'm sure you can' get 3/8 25mm barbs?
you can get 3/8 25mm chap but very few stock it, it took me a while to find a couple, they have to be in bspp and then use ptfe tape to make an airtight thread seal.
19mm is the biggest you will get using the tapered thread fittings.
Never realised you could mate. Had a look but I can't see any. Would have come in handy years ago when I had my first catch can on the old s3. Ended up doubling up on hoses to do a pikey bodge.
You can get anything these days , one just needs to know where to look...
I mess around with Kubota tractors aswell as a hobby so allways need replacement hydraulic hoses and fittings etc, a lot of early 80's kit uses similar size fittings so just sourced them that way.
I've decided to go with a dual can set up and fitted the first part today replacing the PCV (ignore how dirty the engine/bay is, that's a job for next week!):


I'm sure I've noticed a difference already. Car feels smoother when idling and starts up better.

I've got another can to go between the rear crank case and turbo. I've got a heat shield around my induction kit and will be fitting the can in that area. I've also got a funk motorsport turbo blanket to help keep temps down. Will see how it works and give some feedback once I get around to fitting it!!
looks like your half way there chap , what setup are you going to use for the other side of the get's really warm on the exhaust side even with a turbo jacket and heatsheild.
Just be aware that if you are going to be routing the return back in to the intake pipe or turbo then make sure it not hot air going back in as it will just increase the cold air temp and almost cancel out any benefits that you may have gained so far.
That's why I decided to keep the setup all over on the manifold side , just keep the heat under control really, when I had a catch tank on the exhaust side even with a heat shield , the tank got very warm indeed , probably too warm really and all that heated air was going straight back into the TIP , worse than driving around on a very hot day.

anyway , good work so far chap , i'll lookout for you next update.

I've just bought a cheapy off eBay for now to experiment with. It's going to go crack case to OCC then either go back into the TIP as you have done or have a breather filter fitted on the return line and vent to atmosphere.
Hi there. Interesting thread. Will subscribe. What's the mileage on your motor?

Other than the visual and inspection things you described any other systems.
Sorry my last sentence should have read "....and other symptoms? "
Rob if you get chance Chuck a link for the place you bought the 25mm barbs from, it'll be handy for anyone wanting to do this.
I'm going to start making up some kits shortly inc the barbs and turbo blanking plates etc for anyone looking to do similar fitting.
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That's a good idea tbh mate.

What you going to include in the kits?
I think the best way is to offer a full kit really for a full pcv delete, no point just doing half the job.
I'll base it around what I have fitted with a few enhancement options , but same format basically as it works very well.
may offer some parts aswell , not 100% yet on weather that's really worth doing though......
This would be superb bud, very interested if u sort it! minus the braided hoses...
The hoses are not fully braided , I just had some braided covering from the first install and decided to go a bit blingy and just slide it over the new setup.
Kit's will give buyers several hose options inc all alloy tubing for those who don't want to go the silicone hose route.
Interested in a kit, any idea of a rough price?
I've made a few improvements to one area but it wont make effect the total cost of the kit, i'm just getting some final costings worked out , wont be cheap to be honest as some parts I cant really supply for any less than my purchase price, but wont be that expensive either, just depends on how much you wish to improve the problem to start with and the parts i'm going to include in the kits are good quality kit no cheap tat.....

i'll put of the costing shortly along with options .

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So, catch can has been on the car for a month now. This is what came out of it today:

Catch Can

Definitely worth putting one on your car if you haven't done so already.
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yep, looks about right chap and just think you have saved all that plus other junk going back into the engine........if owners only new what was going on inside there PCV systems....have you noticed your car running smoother now aswell , much more crisp throttle response aswell.
It's all a win , win situation really.
The IC's will be the crucial point too, i'm taking my bottom hoses of next week to see what's been occurring in them since fitting the new setup.

I'm not expecting a totally oil free episode at this time as there was probably a small residule amount left in them , but , if its half or better of what I drained out last time then that's a winning situation.
I plan on removing them completely shortly for a full cleanout anyway, but It proves the system works and work very well.

Definitely noticed a difference in how the car runs. It’s a lot smoother now and I was surprised at how much junk was in the can after only a month.

Going to be emptying it on a monthly basis now.

I’m very interested in what comes out of your IC’s now you’ve got a can on the car. I’m going to put my new ones on in the next couple of weeks and don’t really want them getting clogged up. Be sure to post up your findings.
I'm very confident the amount will be very small really, as I have only been draining both sides by means of dropping the bottom hoses until now, there was allways going to be oil residue left clinging to all the surfaces inside the IC's, only a full clean and flush out will remove all the last nasty stuff.
As I am using a full setup there should be almost zero levels of contaminates going back into the IC's and intake manifold.
When I pulled the turbo intake pipe last week to check , there was no sign of all that previous oil going back into the system, all nice and clean etc, really proves the point now that by getting the pcv sorted out properly both front and back issues are sorted out.
All the bypass gases and contaminates from the crankcase now go straight to the catch tank port 1 , the valve cover vent goes to port 2 and then the return vapours to the turbo intake pipe......less oil and other nastiness.
Its not totally contaminate free but not far off.
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You’ve done a good job on that set up.

I’ve bought a cheap can from eBay to have a mess about on the turbo side.

I expect I will probably end up ditching it all in favour of a set up like yours in future though
So, catch can has been on the car for a month now. This is what came out of it today:

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Definitely worth putting one on your car if you haven't done so already.

Thanks for sharing.

Maybe a silly question but I assume the thing we are trying to stop isn't just gunk, but also any oil?
Essentially yes. We’re trying to catch any contaminants and stop them from re-entering the inlet system.

Unfortunately the way the PCV system is set up on our cars it drags unwanted blow by gases (containing oil, fuel vapours etc) back into the turbo, intercoolers and inlet manifold. This leads to carbon build up and effects performance, driveability and economy.
Essentially yes. We’re trying to catch any contaminants and stop them from re-entering the inlet system.

Unfortunately the way the PCV system is set up on our cars it drags unwanted blow by gases (containing oil, fuel vapours etc) back into the turbo, intercoolers and inlet manifold. This leads to carbon build up and effects performance, driveability and economy.

Ok thanks.

Makes sense. So whilst we want to stop OIL also entering, I assume that oil never makes it back to where it should go.

So where I am trying to get to is say that the catch can would NOT INCREASE oil consumption - because it's stopping it getting to where it should have never got?
Oil consumption and the PCV are two separate issues, but are linked by the nature of the design.
PCV design effects all internal combustion engines, some more than other , tfsi in particular , fsi also but to a lesser degree.
Oil consumption is a different issue but has connections to the PCV , so can be linked with the tfsi engines as fitted to VW group engines etc.
The catch can I have does have an option to install a return line back to the oil drain line from the turbo. However, I think this defeats the purpose of the can itself.

While having a can could potentially increase oil consumption i think it would be minimal