Go Back  AudiWorld Forums > Audi Models > Audi A4 > A4 (B5 Platform) Discussion
Reload this Page >

Boost leak in back of motor below 3 way breather hose

A4 (B5 Platform) Discussion Discussion forum for the B5 Audi A4 produced from 1995-2001 B5 FAQ

Boost leak in back of motor below 3 way breather hose

 
Old 01-29-2013, 02:46 AM
  #1  
AudiWorld Member
Thread Starter
 
Join Date: Apr 2006
Posts: 136
Default Boost leak in back of motor below 3 way breather hose

So I got a leak the other day that started making a whistle from the engine compartment when the car gets into boost. I had made a pvc fitting to go in the turbo inlet pipe and hooked it up to the compressor at 10psi. I can hear air escaping from the back of the motor somewhere of which I first thought was the 3 way breather hose (06B 103 221)so I took that off and the rubber was so soft on the back downside that I put a hole in it instantly. Got a new part and installed, but that wasn't my main culprit as I can still hear air escaping from somewhere around the bottom or below this hose. I am having a hard time feeling it and locating it. Is there another common fail point back there or maybe trick I can use to be able to see where it is leaking?
dhbiker1 is offline  
Old 01-29-2013, 06:05 PM
  #2  
AudiWorld Newcomer
 
Join Date: Jan 2013
Posts: 9
Default

Originally Posted by dhbiker1 View Post
So I got a leak the other day that started making a whistle from the engine compartment when the car gets into boost. I had made a pvc fitting to go in the turbo inlet pipe and hooked it up to the compressor at 10psi. I can hear air escaping from the back of the motor somewhere of which I first thought was the 3 way breather hose (06B 103 221)so I took that off and the rubber was so soft on the back downside that I put a hole in it instantly. Got a new part and installed, but that wasn't my main culprit as I can still hear air escaping from somewhere around the bottom or below this hose. I am having a hard time feeling it and locating it. Is there another common fail point back there or maybe trick I can use to be able to see where it is leaking?
Yes, under the intake there is a breather tube.
http://www.ecstuning.com/Audi-B5_A4-...ssions/ES5942/

It's a common fail part and if the symptoms are as you described, then it's almost certain that this part is the culprit. With age it crumbles very easy. To replace the T hose that you replaced, you have to disconnect that hose from this breather tube. In doing so you may have cracked it. Not your fault, it happened to me as well. It just crumbled when I touched it, it could have happened to you. My cylinder head was off when it happened to me so I was able to see it crumble, you may not have if your intake was on.

It's as simple as pulling the clip off and pulling it out.
98A4TurboAWD is offline  
Old 01-30-2013, 03:48 AM
  #3  
AudiWorld Member
Thread Starter
 
Join Date: Apr 2006
Posts: 136
Default

The back downward fitting of the breather I replaced looks like it fits over and clamped to a hardpipe that continues to go further down below the intake. Does the hard pipe go bad or are you saying there is another rubber piece below the hardpipe that fails? I couldn't see very much down there maybe i'll have to take off the intake manifold to inspect some more.
dhbiker1 is offline  
Old 01-30-2013, 05:07 AM
  #4  
AudiWorld Newcomer
 
Join Date: Jan 2013
Posts: 9
Default

Originally Posted by dhbiker1 View Post
The back downward fitting of the breather I replaced looks like it fits over and clamped to a hardpipe that continues to go further down below the intake. Does the hard pipe go bad or are you saying there is another rubber piece below the hardpipe that fails? I couldn't see very much down there maybe i'll have to take off the intake manifold to inspect some more.
It isn't easy to see, but you can get the tube off without pulling the intake manifold. There is also the hose you mentioned (the 3rd hose we haven't mentioned that would go into the T hose you replace), but that, I think, is a far less likely culprit.

The breather tube goes bad and just cracks everywhere. Once you have it out, you'll see why. It's too pieces put together and "plastic welded" leaving a bunch of room for splitting. There is also a seal where it goes into the engine that could have shredded.

You will want to pull the 3 screws out that hold down the coolant tank and move that out of the way. Once you do you should be able to finnagle your way down there and loosen that T hose clamp holding the tube, and also easily remove the clip that holds it down.
98A4TurboAWD is offline  
Old 01-30-2013, 05:09 AM
  #5  
AudiWorld Newcomer
 
Join Date: Jan 2013
Posts: 9
Default

This is slightly different from my 98 but it's the same process and part, it just has a different design.

This guy put together a good video
98A4TurboAWD is offline  
Old 01-31-2013, 02:17 AM
  #6  
AudiWorld Member
Thread Starter
 
Join Date: Apr 2006
Posts: 136
Default

Mine was very similar to the youtube video and must be a little different than the part you led me to on ECS website. I was able to get to it all by propping the coolant reservoir out of the way. Starting at the bottom of the hardpipe piece that comes down from the breather hose (06B 103 221) that I originally mentioned in the first post, there is a T fitting (058 103 247). Another side of the T goes to the L shaped hardpipe (06A 103 213) that connects into the crankcase with spring clip and has O ring on it. The 3rd side of the T goes to a slightly S shaped piece of tubing (058 103 221) that goes up to the cluster of vacuum lines/components on top of the intake manifold. I found that the S shaped piece of tubing had a 1" slit in it and was looking very soft and worn out in general. I removed it as one with the T and L shaped hardpipe, which also broke where it goes into the engine. The only thing that I question is that I didn't think I heard the boost leak coming from where I found the tear, but I am going to get all three of these parts from Audi today and hope it clears my problem. One thing I would mention to be careful with is to check if your hardpipe breaks off because the pieces that broke off mine ended up falling down into the engine and took me some time rigging up vacuum sections to get them out.

Thank you for pointing me in this direction and hopefully this may help someone else. Just to mention my car is a 2001 AWM engine code.
dhbiker1 is offline  
Old 02-07-2013, 12:26 PM
  #7  
AudiWorld Member
Thread Starter
 
Join Date: Apr 2006
Posts: 136
Default

UPDATE: This did not fix all of my problem as after completing this I still had a very noticeable whine when in boost that sounded like a dentist drill and I believed was my turbo going bad. Yesterday I ordered a K04 center cartridge from G-Pop Shop and today when I took out the airbox I hooked up the air to the turbo inlet pipe and noticed that there was still a leak at the back of the motor. From what I can tell there is some sort of sensor below the three way crankcase breather hose right behind the valve cover. This sensor piece looks to be bolted in and there is also an aluminum piece that has 3 torx bolts going down vertical into it. After spraying some soapy water and feeling around more, it appears there is quite a leak right below or at the bottom of this sensor area.

Any help on what this is and what might be leaking here?
dhbiker1 is offline  
Old 02-08-2013, 01:37 AM
  #8  
AudiWorld Member
Thread Starter
 
Join Date: Apr 2006
Posts: 136
Default

I took off the sensor (C271300702) and there is a half circle shaped cutout in the engine housing that my thumb just fits into. I believe this is where air is leaking. Does anyone know what this is and how to attack it? I'm assuming the valve cover has to come off and there is something inside. I didn't look that closely yet but i'm also guessing the head gasket is down lower than this..
dhbiker1 is offline  
Old 02-08-2013, 06:53 AM
  #9  
AudiWorld Member
Thread Starter
 
Join Date: Apr 2006
Posts: 136
Default

Looks like the problem is a cam chain tensioner gasket. There is a half moon rubber seal and a metal gasket roughly 5" long. I'm hoping this is causing the dentist drill whine and that my turbo is actually fine.
dhbiker1 is offline  
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
ECS Tuning-Audi
A4 (B8 Platform) Discussion
19
07-16-2018 09:02 AM
raiderrider
A8 / S8 (D3 Platform) Discussion
12
09-08-2015 05:46 AM
audijim113
A8 / S8 (D3 Platform) Discussion
0
09-03-2015 01:22 PM
ECS Tuning-Audi
A4 (B7 Platform) Discussion
0
09-01-2015 09:16 AM
ECS Tuning-Audi
Audi A5 / S5 / RS5 Coupe & Cabrio (B8)
0
09-01-2015 08:27 AM


Thread Tools
Search this Thread
Quick Reply: Boost leak in back of motor below 3 way breather hose


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: