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

[SHAKING STEVENS]

As of right now, I just have it dumping out besides the bellhouse. In the VERY near future, I will be going with Daniels suggestion and running it attached to the exhaust (since the exhuast flow will create a constant vacuum)

In theory it makes good sense

Apologies for digging this up (2012) but i did this last week. Zimms and Dougy Fresh's opinions contradict and I dont understand the vapour dynamics enough to know which one is right.

At the moment I just have a 1" heater hose connected to my new (non crumbly) plastic pipe that comes out the top of the oil filter housing. As zimms suggested this goes straight to the t on the rocke rand down to atmosphere by the bell housing. Do I still need the line and check valve connected to the inlet to keep the gases going the right way? can someone explain whats going on here? At the moment it's plugged and i sacked the check valve off.

thanks

[Charles.waite]

i attempted this a few weekends ago and gave up. reason being i couldn't easily reroute my aftermarket oil catch can drain back valve to return to the engine. bought the 034 breather hose adapter and realized i should have went AN fitting with 90degree elbow. no way i can fit a reducer and 90 degree in there. decided to do this after i go turbo upgrade. also didn't want a check engine for SAI insufficient flow.

great write up btw. took me a while to figure a lot out. basically once you start ripping things out you figure it out. also so much roomier if i did complete the entire procedure. couldn't have even thought to start this without this write up.

one question i have though is, off my suction jet pump Y fitting, there is a hose with a thick all rubber PCV valve type thing that is all chewed up. it can be removed. what does it look like when its new? i read postings that state it is only a dump hose, but there is obviously a PCV check valve in mine. if anybody is willing to trade 034 breather adapter nipple for IE AN fitting type let me know.

Is it either of these?



You're a 2002 right? That pic is a 2004 so yours is probably different...

Also pardon the coolant everywhere. Had a bit of an accident with the coolant bleeder valve on the hardline above the IM. Forgot to turn the engine off when I cracked it open...

[SHAKING STEVENS]

Is it either of these?

You're a 2002 right? That pic is a 2004 so yours is probably different...

Also pardon the coolant everywhere. Had a bit of an accident with the coolant bleeder valve on the hardline above the IM. Forgot to turn the engine off when I cracked it open...

No. Starting from the top of the oil filter housing, follow the 90 degree plastic tube to the end. this will then join straight onto another pipe, on this pipe there is a 't' going up to the inlet manifold (the pipe has a check valve at the opposite end to the 't'). the check valve doesnt look like the regular check valves, it's inside the pipe.
I have a 2003 so i removed the same as you pic, just not sure if i have to worry about the crankcase vent line not having vacuum support from the inlet manifold. thanks.

[SHAKING STEVENS]

Also pardon the coolant everywhere. Had a bit of an accident with the coolant bleeder valve on the hardline above the IM. Forgot to turn the engine off when I cracked it open...

it's times like those you wish you'd put your safety glasses on, although it helps if you have the reactions of a panther (saved my fingers from the angle grinder a few times)

[scubagli]

I did this, as described, I'm getting po441, evap code can anyone chime in and let me know where I went wrong?


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[SHAKING STEVENS]

I did this, as described, I'm getting po441, evap code can anyone chime in and let me know where I went wrong?


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I also got this #16825, i put a check valve on after th evap purge solenoid, cleared the code and so far it has stayed away. Im not sure if this is a related solutio though.
What did u do with yours, leave it open to atmosphere without the check valve?

[scubagli]

Yes...Same code, I'll give the Check valve a try. Thanks


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[BARRY]

Is it either of these?



You're a 2002 right? That pic is a 2004 so yours is probably different...

Also pardon the coolant everywhere. Had a bit of an accident with the coolant bleeder valve on the hardline above the IM. Forgot to turn the engine off when I cracked it open...

my 2002 B6 has entirely different routing for things than most people in this thread. that black chewed up KNUB at the bottom of the pic. it is a PCV valve of some type. i assume it is the same dump hose like most of you have, but mine has a PCV within it.

[walky_talky20]

This guy (the housing):

http://www.ecstuning.com/Audi-B6_A4-...ses/ES2070655/

And this guy (the PCV bleeder valve):

http://www.ecstuning.com/Audi-B6_A4-...ion/ES2093820/

Alternatively you can replace the PCV valve with an all-metal version from 034:

http://www.034motorsport.com/engine-...t-p-21834.html

And you probably should replace that rubber "S" hose at the same time (if you are keeping the Suction Jet Pump and all that):

http://www.ecstuning.com/Audi-B6_A4-...oses/ES277547/

Or, again, the 034 replacement (which is actually half the price):

http://www.034motorsport.com/engine-...e-p-21868.html

And if you're going through all the trouble to make it work right, make sure your Suction Jet Pump isn't clogged up - it probably is. In your design, the flow through the SJP is the PCV vacuums source. The oil and general PCV "nastiness" like to clog up the small passage in the SJP. No matter how good you fix up that housing, bleeder valve and hoses - if the SJP is clogged it is all for nothing because none of it will get any flow.

[Matt Devo]

And if you're going through all the trouble to make it work right, make sure your Suction Jet Pump isn't clogged up - it probably is. In your design, the flow through the SJP is the PCV vacuums source. The oil and general PCV "nastiness" like to clog up the small passage in the SJP. No matter how good you fix up that housing, bleeder valve and hoses - if the SJP is clogged it is all for nothing because none of it will get any flow.

which way should the SJP flow? I just replaced all my PCV stuff but not the SJP, should probably test it

[old guy]

Flow is always toward the vacuum source (intake manifold) for any check valve.

[SHAKING STEVENS]

i removed the sjp, associated pipework and any pcv connections to the inlet manifold. i ran a 1" line from the crank breather straight up to the vc connection, teed it there and then sent one line down the bell housing (venting at atmospheric pressure).

quoting walky talky from his b5 thread:

The suction jet pump (SJP) is used as a vacuum amplifier for the brake booster.... It uses flow from the PCV system to create the effect...Vacuum to the crankcase is important to evacuate blow-by emissions, and a properly working PCV system is even more important on a turbocharged car due to the increased blow-by

firstly, i dont have the required understanding and shouldnt have tossed the sjp in the corner, although i read everyone's expanding detail (absolute gtr, walky talky, old guy etc.) clearly i hadnt soaked it all up in time.

3 questions:
1) i am concerned about 'blowby' and my engines lack of ability to deal with it? Given i just have a 1" line going up the the vc and then to atmosphere (as another member on here recommended), can i just re instate the pcv check valve (better still replace with ecs improvement), the pcv rubber 't' and the line back to the inlet manifold? so i have no vacuum source helping the crankcase breath, but surely just reinstating the pcv check valve without the sjp will just pull crank vapours into the inlet manifold (except when under boost). i am confused.

2) Given im happy with the current braking abillity (with no sjp) should i be concerned with lasting reliability? the last thing i want is sudden catastophic loss of the braking system.

3) having no evap purge system will make me run lean. But is this significant and do i need to worry about it? will the maf not provide the compensation, surely gas tank contributions are minimal. I assume a decent remap would address this, but realistically that's not going to happen for a year or so, maybe two.

a solution, however complicated, is appreciated and will be implemented, i can put some of that stuff back in no problem.

thanks people

[SHAKING STEVENS]

Yes...Same code, I'll give the Check valve a try. Thanks


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oh and leave the soleniod electrical connection plugged in too, as absolutegtr mentions.
i wouldnt over simplify the pcv vac/sjp stuff until the experts can direct us on the significance of these systems- dont make the same (potential) mistake i did. i favour reliability over performance any day im afraid, both are preffered though!

[scubagli]

I ran a 7/8 hose from block to a t at the valve cover to a port in the down pipe.


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[SHAKING STEVENS]

I ran a 7/8 hose from block to a t at the valve cover to a port in the down pipe.


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ok so i need a vac source plugging back into the end of the oil vapour (crank and vc) collection line. is your exhaust stock without modification or am i going to have to remove the downpipe and get a slanted tube welded in? fuks sakes.
test pipe arrives 2mo, how about i drill out the 2nd lambda boss and slap the fumes into there? frickin lambdas, i should only need one once the cat is gone.

cheers for the help dude.
my evap 16895 came back on, im gonna leave it until i get it remapped, im not arsed really.

[old guy]

Normally I don't like responding to these type of threads because I really don't condone the "ripping it all out" approach to solving vacuum or boost leak issues. I'm a firm believer that if you take the time to fully understand the function of the various components that you will find it easier to correct the problem instead of ripping everything out only to find that you have created new issues (Stinky blow off odors, CEL's, etc). I don't know if you have seen this or not. Clicky click. It was my attempt to explain how all that "stuff" functions. Now on to your questions:

3 questions:
1) i am concerned about 'blowby' and my engines lack of ability to deal with it? Given i just have a 1" line going up the the vc and then to atmosphere (as another member on here recommended), can i just re instate the pcv check valve (better still replace with ecs improvement), the pcv rubber 't' and the line back to the inlet manifold? so i have no vacuum source helping the crankcase breath, but surely just reinstating the pcv check valve without the sjp will just pull crank vapours into the inlet manifold (except when under boost). i am confused.

If you want to provide positive block ventilation at a minimum you will need to do the following: Connect the crank case to the valve cover to equalize the upper and lower block pressures and vent the line with the block breather valve (PCV). This line should be connected to the intake manifold. Essentially return it to the OEM configuration. Next you will need to put back the PRV (pressure regulating valve) either on the back of the valve cover or on the TIP and connect it to the back of the valve cover. Again, essentially returning it to the OEM configuration. Either position will suffice. This will both protect the block from boost pressurization and provide positive block ventilation whenever the manifold is under vacuum.

2) Given im happy with the current braking abillity (with no sjp) should i be concerned with lasting reliability? the last thing i want is sudden catastrophic loss of the braking system.

You will not experience "catastrophic loss of braking" but under certain conditions you could definitely have a significantly reduced amount of brake booster aid at inopportune times. Your brakes will still work but will require a lot more pedal pressure to stop.

3) having no evap purge system will make me run lean. But is this significant and do i need to worry about it? will the maf not provide the compensation, surely gas tank contributions are minimal. I assume a decent remap would address this, but realistically that's not going to happen for a year or so, maybe two.


a solution, however complicated, is appreciated and will be implemented, i can put some of that stuff back in no problem.

Your ECM can easily handle the A/F adjustment from removing the evap system controls. What it can't do is to remove the emission of smelly hydrocarbon fumes that the open evap system will be emitting or the CEL from running an open tank vent.

[walky_talky20]

i removed the sjp, associated pipework and any pcv connections to the inlet manifold. i ran a 1" line from the crank breather straight up to the vc connection, teed it there and then sent one line down the bell housing (venting at atmospheric pressure).

quoting walky talky from his b5 thread:

The suction jet pump (SJP) is used as a vacuum amplifier for the brake booster.... It uses flow from the PCV system to create the effect...Vacuum to the crankcase is important to evacuate blow-by emissions, and a properly working PCV system is even more important on a turbocharged car due to the increased blow-by

firstly, i dont have the required understanding and shouldnt have tossed the sjp in the corner, although i read everyone's expanding detail (absolute gtr, walky talky, old guy etc.) clearly i hadnt soaked it all up in time.

3 questions:
1) i am concerned about 'blowby' and my engines lack of ability to deal with it? Given i just have a 1" line going up the the vc and then to atmosphere (as another member on here recommended), can i just re instate the pcv check valve (better still replace with ecs improvement), the pcv rubber 't' and the line back to the inlet manifold? so i have no vacuum source helping the crankcase breath, but surely just reinstating the pcv check valve without the sjp will just pull crank vapours into the inlet manifold (except when under boost). i am confused.

2) Given im happy with the current braking abillity (with no sjp) should i be concerned with lasting reliability? the last thing i want is sudden catastophic loss of the braking system.

3) having no evap purge system will make me run lean. But is this significant and do i need to worry about it? will the maf not provide the compensation, surely gas tank contributions are minimal. I assume a decent remap would address this, but realistically that's not going to happen for a year or so, maybe two.

a solution, however complicated, is appreciated and will be implemented, i can put some of that stuff back in no problem.

thanks people

The SJP has 3 ports:


The left one (flared end) has the check valve built in. That port goes to the brake booster.
The right one goes the intake manifold directly. That port will see full vacuum and boost.
The bottom one goes to the PVC bleeder valve.

The flow between the manifold and brake booster is in 1 direction. The SJP blocks boost from going to the brake booster line. The flow between the manifold and the PCV bleeder valve is BOTH directions (indicated by the Blue and Green arrows). Blowing into the RIGHT port will allow free flow out the bottom port and nothing out of the left port. Suction on the right port will cause suction on BOTH the left port and the bottom port (block each one to check flow individually on the other). If the flow is very limited to the bottom port (ie: hard to blow through), or it is plugged completely, replace it.

NOTE: Only the early B6 1.8T's (up to VIN 8E-3-040000) use the SJP as vacuum supply to the PCV system. The Later models (From VIN 8E-3-040001) connect the PCV bleeder valve directly to the manifold with nothing in between. I'm assuming this was to eliminate the known issue with the SJP clogging up with nasty PCV crap and blocking PCV bleeder flow. The Later models put only "fresh" air through the SJP and thus eliminate that issue. In that configuration the bottom port connects instead to the TIP through a small metal hard line.

To answer your questions:
1)You can't reincorporate the PCV bleeder valve if the system is still "venting to atmosphere". At idle the bleeder valve would pull unmetered air right from the atmosphere and into the intake manifold, completely bypassing the MAF. If your various vent lines just dumped into the TIP (usually via a "pancake valve"), THEN you could reincorporate the manifold vac source to your PCV system.

2)No, lots of people delete the silly things. I've noticed no difference at all after deleting my SJP. The 1997-1999.5 Audi A4 1.8T with manual transmission did not even have an SJP, only the Automatic cars got it prior to the 2000 model year. All of those cars worked just fine without it.

3)You have a wideband O2 sensor. As such, the ECU has omniscient knowledge of the AFR. IF it sees it going lean, it will increase the fuel trim to reach the target AFR. The EVAP contribution adds minimal enrichment. No worries.

EDIT: Took too long gather my thoughts (pretty normal for me, I'm afraid) and old guy covered everything quite nicely.

[Seerlah]

Hey Walky, I just did my vacuum delete and have it so there is just a hose going from the brake boost to where the L-breather hose on the IM is (by throtte body). Should I place a check valve onto this? Only lines left is the brake booster to IM and dv to IM. Is there a problem with this?

For my crankcase ventilation, I have the pcv valve located under the IM simply venting to the atmosphere. Since that is the only line left under there, I am routing the ventilation conjunction that connects at the 3 way breather valve on the valve cover to under the car via radiator hose for now (thinking about placing a filter on the end, just because). Eventually, I will delete that too and do a SS -10an exhaust dump via Vibrant E Scavenger and block breather adapter. But is there any issues with the way I am going about it?

[old guy]

There is one thing to consider with the flow indicated by the green arrow. Flow in that direction isn't really possible if you consider the upstream connections. On an "02 it connects directly to the PCV valve. The PCV valve will only allow flow toward the intake manifold. On an '03 or later it connects to the TIP and is protected by a check valve that also only allows flow toward the manifold. Consequently all the flow is only toward the intake manifold.

[old guy]

Hey Old Guy, I just did my vacuum delete and have it so there is just a hose going from the brake boost to where the L-breather hose on the IM is (by throtte body). Should I place a check valve onto this?

Yes. It will add an additional layer of protection for the brake booster that was never designed to check full boost. In the OEM configuration it is protected by a check valve.

[Seerlah]

I see what you did there . Thanks! I also edited my last post with another inquiry, if you don't mind answering.

[old guy]

For my crankcase ventilation, I have the pcv valve located under the IM simply venting to the atmosphere. Since that is the only line left under there, I am routing the ventilation conjunction that connects at the 3 way breather valve to under the car via radiator hose for now (thinking about place a filter on the end, just because). Eventually, I will delete that too and do a SS -10an exhaust dump via Vibrant E Scavenger and block breather adapter. But is there any issues with the way I am going about it? And I would like an answer to the check valve inquiry on the brake booster line.

There is no reason to keep the PCV if it is venting to atmosphere. The only reason to keep the PCV is to prevent the boost pressure from entering the block. If it isn't connected to the intake manifold it can't receive a boost signal. I would recommend putting a check valve between the intake manifold and brake booster for another level of protection. The OEM configuration had a check valve to protect the brake booster. The brake booster wasn't designed to handle full boost. It has a check valve but an additional layer of protection is a good idea.

[Seerlah]

I was actually just using the pcv as a plug. Should I get an actual plug for that port, then?

[old guy]

I was actually just using the pcv as a plug. Should I get an actual plug for that port, then?

Absolutely not!!! the PCV is a one way valve. It is allowing the block pressure to vent out. If you plug it the block will not be able to vent. Leave it in place or just run an open line. Either way you are doing the same thing.

[Seerlah]

I have an AWM (B5), with the other pcv gone (pancake valve). My other PVC (pancake valve) would be on the tip itself, while the AMB guys have it on the back of the valve cover. That pcv is gone. If I plugged the one by the block breather (one we are referring to), the blow by would just keep going up the pcv piping to the 3 way valve cover breather hose, then into the atmosphere (I have nothing attached to the 3 way breather currently, on the exhaust side of the engine).

Also, my car is currently on jack stands. I'm doing some stuff to it and this is part of the stuff. I just want to confirm I am doing it right before I turn my car over.

[old guy]

If I am understanding you correctly you are connecting your lower block breather to the valve cover breather and venting both to atmosphere. If that is correct then yes it will work to vent the block. What it won't do is purge the block vapors with fresh air.

[Charles.waite]

The pancake is the prv not pcv.

[Seerlah]

Thanks for the correction. ECS listed it as the PCV valve also, but I always called it the pancake valve (never knew the name of it). Thought ECS had it correct, and we had two pcv valves and not one (ECS link).

So?
PRV: Pressure release valve
PCV: Pressure control valve

[scubagli]

ok so i need a vac source plugging back into the end of the oil vapour (crank and vc) collection line. is your exhaust stock without modification or am i going to have to remove the downpipe and get a slanted tube welded in? fuks sakes.
test pipe arrives 2mo, how about i drill out the 2nd lambda boss and slap the fumes into there? frickin lambdas, i should only need one once the cat is gone.

cheers for the help dude.
my evap 16895 came back on, im gonna leave it until i get it remapped, im not arsed really.

I have a 3" DP, got the exhaust port from jegs, 45 degree o2 sensor port, with an AN fitting...


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[walky_talky20]

There is one thing to consider with the flow indicated by the green arrow. Flow in that direction isn't really possible if you consider the upstream connections. On an "02 it connects directly to the PCV valve. The PCV valve will only allow flow toward the intake manifold. On an '03 or later it connects to the TIP and is protected by a check valve that also only allows flow toward the manifold. Consequently all the flow is only toward the intake manifold.

Certainly. The photo is merely depicting the behavior of the SJP apart from the car. The discussion of "flow" was in reference to how to bench test it. On a good SJP, there will good flow in the "green" direction. On a clogged one, it won't flow. Assuming all components are good, there won't be any "flow" in the green direction under normal circumstances.

That is a good point to make should someone attempt to test it without completely disconnecting it.

[old guy]

Certainly. The photo is merely depicting the behavior of the SJP apart from the car. The discussion of "flow" was in reference to how to bench test it. On a good SJP, there will good flow in the "green" direction. On a clogged one, it won't flow. Assuming all components are good, there won't be any "flow" in the green direction under normal circumstances.

Good point. I was commenting on application rather than a test method. Here is a pic as to how it works. The flow of air coming through the venturi section creates a stronger vacuum pull on the brake booster port. This particular SJP is from a BMW but the function is the same. The "F" connector for the BMW is connected to the PCV line on an '02 and to the TIP on an '03 or later for our 1.8T motors.

Thanks for the correction. ECS listed it as the PCV valve also, but I always called it the pancake valve (never knew the name of it). Thought ECS had it correct, and we had two pcv valves and not one (ECS link).

So?
PRV: Pressure release valve
PCV: Pressure control valve

ECS nomenclature is incorrect. A PCV is a one way valve. The PRV (aka pancake or Pressure Regulating Valve) is a two way valve. It limits the air being pulled into the block and acts as a blow-off valve if the block becomes excessively pressurized.

[SHAKING STEVENS]

I ran a 7/8 hose from block to a t at the valve cover to a port in the down pipe.

if you do this, where does the volume get fresh air from?

[SHAKING STEVENS]

If you want to provide positive block ventilation

I only want to, if it significantly helps mechanical performance or reliability. Is this a fuss of over nothing? (caused by me)

i cant see why having a vacuum on the 'volume' is important, isnt piston windage negligable? as long as I've got a release for any positive pressure built up (via atmosphere/catch can) my breather system should be adequate for normal reliable, stock powered operation? dumping that (partially burnt) dirty oil vapour mix back into the inlet is not what my engine needs, like me mixing my cereal with horse poo....

This will both protect the block from boost pressurization

current layout will not allow boost pressurisation since it's connected to atmosphere

provide positive block ventilation whenever the manifold is under vacuum

why does the block need to be under vacuum?

a check valve will be installed on brake booster line.

thanks old man, if you need an adopted son i want first refusal, and dont worry, i eat toast for breakfast.. would happily move to the US and get a job there.

[old guy]

The purpose of the block ventilation system is twofold. It relieves internal pressure from blow-by gasses and it also purges these concentrated blow-by gasses with fresh air. If you simply run an open dump you will not get the benefit of any purge air in the block. Can you do that? Certainly. Lots of guys on here are running open dumps. Should you do that? In my opinion, no.

The 1.8T motor is already at a disadvantage with high oil temperatures from the turbo and a fairly small oil capacity that both contribute to sludge conditions. Why put an additional burden on the motor by allowing blow-by gasses to accumulate in the block? If you are concerned with burning the blow-by gasses you can always add a catch can and filter them out. There is absolutely no performance down side to leaving the basic block ventilation system intact. There are consequences to allowing the blow-by gasses to concentrate. I already mentioned the increased possibility of sludge formation. Another down side is the caustic effect the blow-by gasses have on the seals and gaskets in the motor.

Moisture control can also become an issue, especially in the winter. An active purge system helps to quickly remove the moisture. Without a purge it will take a lot longer to get the moisture out of the block. If you make a lot of short trips the moisture content will continue to increase until you start to see a chocolatey froth developing.



Virtually ALL motors come with a block purge system. Modern cars typically use a PCV system to vent the block and capture the noxious fumes for environmental reasons. Prior to the PCV systems the purge was provided by a valve cover vent and a road draft tube and the fumes vented to atmosphere. Either way the block was purged. All you are doing is providing a pressure blow off without the purge function.

[waldo1324]

has anyone done this and corrected a vac leak / boost leak?

just curious if its a possible fix for my efing effing effing boost leak.

also- whats your personal preference on breather setup? artmosphere? vac to mani? catch can?

[BARRY]

has anyone done this and corrected a vac leak / boost leak?

just curious if its a possible fix for my efing effing effing boost leak.

also- whats your personal preference on breather setup? artmosphere? vac to mani? catch can?

as old guy stated...venting straight to the atmosphere is bad for our motors. when venting directly to the atmosphere, think of it this way...your engine once shut off is expelling hot air and fumes. once your engine cools down the air will compress slightly and suck outside air through your vent tube back into the engine. since outside air has more moisture than any air that has been in recirculation, you will essentially be adding water in small doses to your oil. water in small doses to your oil will cause sludge and froth. most people think oh my catch can caught all this nasty stuff. in actuality the catch can the first stop to and from the engine and outside air. all that nasty stuff you see in your catch can is water from the outside air being mixed with your engine oil.

i ended up not removing much from my car when i worked on it recently. i had spent maybe 500 dollars in hoses and a catch can with plans to rebuild my entire system. i was planning to have "catched oil" reintroduce itself into the crankcase as an entirely closed system. to be upfront about things, there really is not a good place to drain back the oil aside from adding a secondary crankcase breather. eventually when i go big turbo i will be using the oil drain back tee'ed for my catch can drain back.

another thing most of you don't realize is, adding negative pressure to your crank case is a good thing. negative pressure means less work your pistons and crankshaft have to output to spin. negative pressure promotes positive ring sealing. with a OEM type configuration you are getting close to a neutral environment. with venting to the atmosphere, you honestly need to vent quite more than one port to the atmosphere. at that point eventually you'll get to a situation where more oil is being lost than it is worth doing. my old race car would sign around 9,500rpm so much at the end of a track day, i would be 1 quart short of oil. eventually you learn, recirculating/filtering/whatever is definitely a good thing for your engine in the long run. for your pocket book as well.

[walky_talky20]

I am also proponent of keeping the closed/vacuum system. However, I'm also a proponent of simplifying. In my personal opinion, the later B6 breather system got absolutely out of hand with all the check valves and plastic pipes. Lots of failure points are added. The ideal arrangement IMHO would be the earlier design like the 2002 B6 1.8T, but with direct manifold vacuum source to the bleeder valve like the AEB (97-99 B5 1.8T). That keeps only the necessary parts of the system while eliminating a lot of complexity and possible leak points. And using the 034 silicone/billet parts makes it even better. Again, completely my opinion, and that is how I set up mine as outlined in my B5 Vac "simplification" DIY thread.

[SHAKING STEVENS]

If you simply run an open dump you will not get the benefit of any purge air in the block. Can you do that? Certainly. Lots of guys on here are running open dumps. Should you do that? In my opinion, no.

The ideal arrangement IMHO would be the earlier design like the 2002 B6 1.8T, but with direct manifold vacuum source to the bleeder valve like the AEB (97-99 B5 1.8T). That keeps only the necessary parts of the system while eliminating a lot of complexity and possible leak points.

negative pressure means less work your pistons and crankshaft have to output to spin. negative pressure promotes positive ring sealing. with a OEM type configuration you are getting close to a neutral environment.

thanks for the responses, this kind of wraps this up now. Basically, when zimms666 stated to "remove all that crank vent shit under the manifold" he is far too relaxed in saying so, im not blaming him, i make my own decisions, but this was made in haste.

In summary, if your keeping your motor and want the best for it, i would try and leave the crankcase vacuum and air purge system in place, the hoses are not a massive access hinderance, and you can still remove alot of the other stuff. piston windage on these motors should perhaps be considered with more concern than just 'it's negligable'.

In my (time limited) situation, I'm hoping to put the one way pcv on the outlet breather to atmosphere, thus preventing moist air leakage into the engine volume. In the longer term, afer I've fitted my new milltek exhaust, I will look to re establish the fresh air purge system, somehow, with the bits i have left over. Now i can see why it is important.

Again- cheers for speaking up gents.

[holywar0902]

After doing this vacuum line delete, anyone notice the diverter valve sound different? Mine sounds more crisp, not woooosh but like woosh lol, and no more flutter when I let off in vacuum.

[mcclintock89]

If anyone does this anytime soon, PM me and I will buy your parts you take off if they are still in good shape!