DIY - B6 1.8t - Vacuum line and Check Valve removal/simplification

[b00stleak]

Did you reuse the rubber T that hooked up to the pancake valve? Also did you just run it just like this?

[eSMOOV913]

Did you reuse the rubber T that hooked up to the pancake valve? Also did you just run it just like this?

Correct. Sent mine below car to atmosphere. Never again will i allow that sludge back into my engine. And yes crank breather straight to valve cover “T”


Sent from my iPhone using Tapatalk

[old guy]

Correct. Sent mine below car to atmosphere. Never again will i allow that sludge back into my engine. And yes crank breather straight to valve cover “T”

Just curious. What sludge would that be?

The 1.8T is a port injection engine and consequently the intake ports and valves are constantly being washed. As long as you use a Top Tier gasoline you should not have a problem with any carbon build-up. Here's what my intake ports and valves looked like after 200k miles using Shell gasoline.

Looks pretty clean to me.



The other argument is that the intercooler gets all gunked up and reduces its efficiency. That one is true but probably a lot less than you think. It's barely measurable. Clicky click®

Bottom line is that the best thing for you engine at a minimum is to maintain the PCV/PRV system in place. It keeps the block under vacuum and provides a constant source of purge air through the block to keep the internals cleaner and reduce condensation in the colder weather.

[b00stleak]

The reason the head looks so clean is because that's right where the injector sprays. The actual intake manifold is full of junk, and also every hose connected within the system is caked with dry sludge. Almost looks like dirt. Not too healthy for that to go thru your turbo.

[eSMOOV913]

The reason the head looks so clean is because that's right where the injector sprays. The actual intake manifold is full of junk, and also every hose connected within the system is caked with dry sludge. Almost looks like dirt. Not too healthy for that to go thru your turbo.

Sent from my iPhone using Tapatalk

[b00stleak]

Some quick pics of some of the junk I ripped out.

[old guy]

That is simply not true with a properly maintained PCV/PRV system. I am intimately familiar with the 1.8T. I purchased mine new back in 2003. it now has ~250k miles on it. I do all my own work including turbos, clutches, brakes, heads, suspension, whatever. It runs better than when it was new. And I can assure you that there is no gunk anywhere in my intake system from the air filter to the intake valves. There is a light film of oil coating the intake track and typically a dribble of oil in the intercooler but that's it.

If you have a mess in your intake you have not been properly maintaining your block breathing system.

[eSMOOV913]

That is simply not true with a properly maintained PCV/PRV system. I am intimately familiar with the 1.8T. I purchased mine new back in 2003. it now has ~250k miles on it. I do all my own work including turbos, clutches, brakes, heads, suspension, whatever. It runs better than when it was new. And I can assure you that there is no gunk anywhere in my intake system from the air filter to the intake valves. There is a light film of oil coating the intake track and typically a dribble of oil in the intercooler but that's it.

If you have a mess in your intake you have not been properly maintaining your block breathing system.

Not everyone got to maintain their vehicle from the get.. I replaced PCV system and SJP, and not too far down the road boost leaks. IMO. Delete all that extra shit.


Sent from my iPhone using Tapatalk

[old guy]

What I really dislike about this thread is that a lot of guys read it and take the "just rip everything out" approach without fully understanding the function of what is being ripped out.

Your engine will operate better and be healthier with a properly maintained PCV/PRV in place. Here's a 10 year old thread that may help explain some of the "ripped out" stuff. Clicky click®

[b00stleak]

Yea I bought mine blown up. Pulled the intake manifold off and was in awe at the rats nest of vacuum lines I found under it. I knew right then that there has got to be a way to simplify all of that garbage. A quick search led me right here. I was going to do it anyway even if I had to blaze my own trail doing it. I have never seen such a complicated mess. Even newer diesels aren't this clustered. If it wasn't such a mess, then this probably would not be an issue and this thread wouldn't exist. But it is a mess and this thread does exist because of that. Blame whoever had their head up their butt when designing it. I take the KISS approach when working on stuff. I am educated in how all of this works. I also understand it is for emissions. I will probably run a catch can, maybe. It's not so much about ripping out the PCV just cause. I actually broke one of the crusty lines running to the pancake. And this being my beater, I'm not putting that much money into it.

[old guy]

Yea I bought mine blown up. Pulled the intake manifold off and was in awe at the rats nest of vacuum lines I found under it. I knew right then that there has got to be a way to simplify all of that garbage. A quick search led me right here. I was going to do it anyway even if I had to blaze my own trail doing it. I have never seen such a complicated mess. Even newer diesels aren't this clustered. If it wasn't such a mess, then this probably would not be an issue and this thread wouldn't exist. But it is a mess and this thread does exist because of that. Blame whoever had their head up their butt when designing it. I take the KISS approach when working on stuff. I am educated in how all of this works. I also understand it is for emissions. I will probably run a catch can, maybe. It's not so much about ripping out the PCV just cause. I actually broke one of the crusty lines running to the pancake. And this being my beater, I'm not putting that much money into it.

There is another very important function provided by the PCV/PRV system. This block breathing system provides a constant supply of clean filtered air through the block to actively remove water vapor and block blow by gasses. It also allows the block to operate under a slight vacuum which helps with the ring sealing. Once you remove this purge system the block operates under a slight pressure build up of blow by gasses. This pressure eventually builds up to where it is pushed out of the block.

Or you can run it through a catch can and pat yourself on the back for all of the "gunk" that you collect in the can. Unfortunately most of this "gunk" is a result of removing the purge air function that prevents it from building up in the first place.

Even pre-emission engines maintained a block purge function by drawing air through a filtered breather cap with the vacuum being created by a road draft venturi tube. Removing the block purge air breathing system will definitely not result in a healthier engine.

[b00stleak]

You do realize that a catch can does the exact same thing right? And the gunk I'm talking about is already in the pipes as pictured above. I'm not going to mess with replacing the entire system when I have a catch can sitting on a shelf.

The pcv will help seal the rings if it's working properly. If not, guess what? That pressure is going out somewhere, whether it be the oil pan gasket, valve cover gasket or most likely the dipstick. If its dumped to the atmosphere, it is vented and no pressure will build up. You are right, the old school V8s did use a very simple system that I would leave in place. That's exactly what we are doing with catch cans. Putting in a simple system. Im actually curious if you have even used one. The majority of what it collects is condensation. On my LS1 I hardly get anything collected in the summer, and that's with a larger ring gap to be used with FI/nitrous. The winter I would get a full can every other week.
So pat yourself on the back and keep sitting up on that PCV throne of yours thinking you're all high and mighty, talking down to everyone else.

[old guy]

I apologize If I am coming across as talking down to you. Not my intention.

I do need to clarify that a catch can does not do the exact same thing. I am fully aware that in the winter a catch can collects a lot of condensation. But it's a catch 22;-) The PCV/PRV provides purge air that constantly removes the condensation. Once you remove the purge air the condensation concentrates and is eventually pushed out through the catch can. Thus the higher concentration in the winter.

Edit: And I should also add that you can't compare a catch can on an LS1 with a catch can on a turbo engine. With the LS1 you only need to insert the catch can in the PCV stream so it doesn't disrupt the constant flow of air. With a turbo you don't have that luxury.

[Brisig19]

I'm confused by looking at the finished product diagram. The diagram shows a line going to the crankcase breather over between the intake manifold and the driver front fender well, but didn't we remove the crankcase breather and toss it.? And why is it located there now.?

[b00stleak]

I'm confused by looking at the finished product diagram. The diagram shows a line going to the crankcase breather over between the intake manifold and the driver front fender well, but didn't we remove the crankcase breather and toss it.? And why is it located there now.?

I see your confusion. That is the crank breather on the block. It's #13 in the picture. Hope that helps.

[Charles.waite]

Pulled the intake manifold off and was in awe at the rats nest of vacuum lines I found under it.

I'mma let you finish but if you want to see a REAL rats nest, feast your eyes on the 1970s Toyota 2F engine:

That wasn't even the CARB compliant version which is somehow even worse. The 1.8t really isn't bad, there aren't superfulous or unnecessary lines. If you hate that stuff thats your prerogative, but be aware shit doesn't work as well with that stuff removed...

[b00stleak]

I'mma let you finish but if you want to see a REAL rats nest, feast your eyes on the 1970s Toyota 2F engine:

That wasn't even the CARB compliant version which is somehow even worse. The 1.8t really isn't bad, there aren't superfulous or unnecessary lines. If you hate that stuff thats your prerogative, but be aware shit doesn't work as well with that stuff removed...

It started right up and runs just fine. I'm not really sure what won't work as well. I like these A4s because the motor's not in there sideways and I can get to things to work on them without working against the firewall too much. Same concept as a Cummins. Much easier to do anything on that motor as a opposed to a V8. Apples to oranges, but it makes sense in my mind. That rat's nest was hindering the simplicity of it all to me. It's all gone, the cat too. Quite a bit more room in the bay now. I can appreciate that some guys like to keep it or need to for emissions reasons. I'm just not one of those people. I bet you can also delete all that garbage on that Toyota engine and I wouldn't be surprised if it is common practice. I could be wrong though.

[Afrodeezyak]

Starting to put my build together and have been following this thread.
I am running a diverter and am wondering where the line circled runs to, is it the open port on the N249 valve?

vacuumrouting_LI.jpg

[absolutegtr]

Wow so cool this DIY is still active! 13 years later!

[Randolphj16]

Im trying to do this and i just wanna know. So we dont need the crank case vacuum pump in the drivers finder well? Just vent the crankcase to the air. Also what in (diety's) name is the TIP.

[Ozone510]

Im trying to do this and i just wanna know. So we dont need the crank case vacuum pump in the drivers finder well? Just vent the crankcase to the air. Also what in (diety's) name is the TIP.

Turbo Inlet Pipe BTW, not sure about the rest.

Sent from my Pixel 7 Pro using Audizine Forum mobile app

[javidgunz123]

IMG_2372.jpg
For anyone wanting to keep n249 with everything else deleted. Anyone else done this?


Sent from my iPhone using Audizine Forum

[Crispy222]

Do not put a plug at #1. This will destroy the compressor wheel.

Sent from my SM-S906U using Tapatalk

[Mica_Hiebert]

Is there a reason to looping the ports on the little valves that bolt under the intake manifold vs caping them or leaving them open? On mine the old brittle hose barbs broke off when cutting the clamps off. Need to know if theyll be fine left open.or epoxied shut or if i need new valves and loop the lines as not to cause codes.

[LiL-Booth]

How’s it going, I was doing the sai delete and I was wondering after connecting the brake booster to the manifold what would you do with the brake vacuum pump, does it get plugged or does it just stay open? It would no longer be in use correct or did I miss something?