Convince me this is not the PCV (oil separator)...

[koolade9]

I need a second opinion… Car was burning oil out the back quite badly (think 88 honda crx). First thought, CB, no worries… Well I just cleaned the CB and removed the SAI system. Upon inspection of the PCV, the piston was actually stuck outwards. A slight nudge and it pushed back in and was actuating again. I cleaned the PCV out and the piston seemed to move freely and function properly/better. I cleaned out the PCV lines, TB (which wasn’t too dirty), and everything was re-secured and checked upon reassembly.

More info: The bank 2 valves were all evenly wet, whereas the bank 1 valves looked ‘normal’. Also getting a bit of oil seepage from the bank 2 valve cover. After re-assembly, I’m still having the same issues. Everything is pointing to restriction in the PCV and excess pressure in the rocker covers, forcing oil through the valve seals, and out the gasket. Worst-case, my valve seals are shot, hence my interest in head-work…but I’m having a hard time believing all 4 seals would go bad at the same time on one head, but not the other.

I’m about to order a new PCV, but before dropping the $ on a new one, is there something I could be missing here? I’m open to ideas…

TIA!

[B6JoeS4]

Well if the valves are wet then it has to be oil coming through the PCV since there is no other way for oil to get in the intake.

Maybe check the baffles on the bottom side of the valve covers that attempt to stop oil from even getting out of the valve cover and into the pcv system in the first place. On the S4 they were small stainless plates that created a chamber for oil to condensate. Mine were all sludged up which I think might lead to excess oil getting through.

A remote breather setup would be cool. Not sure the the RS4 emmisions system would cooperate though. It would stop oil from ever getting there in the first place.

[koolade9]

[quote=“B6JoeS4,post:2,topic:4118”]
Very interesting…excellent point! This could tie into my search for a new valve-cover gasket. Audi lists a redesigned valve cover for that side (I think it was that side IIRC). To the tune of $600 at cost… They must’ve redesigned it for a reason (sigh).

A remote breather setup would be cool. Not sure the the RS4 emmisions system would cooperate though. It would stop oil from ever getting there in the first place.

If a new PCV does the trick, I’ve already got a couple ideas for fabbing an open-air ‘catch can’ that could use the oil drain line (zero maintenance) and block off the port on the intake (making it even easier to pull the IM). The challenge will be making it pass a visual inspection, but I’m getting ahead of myself…

[sakimano]

^^^wow…good point about the gasket.

Hey, let’s get NY07RS4 in here. He had some seroius black smoke last year and got a new motor because of it. I wonder if his was the left side

He asked me to order him some of those gaskets as well after he saw you and I talking about that.

[NY07RS4]

Will chime in later today when I’m on a pc. Too hard to type all info from my phone.

[sakimano]

^^^iPhone^^^

[91gl]

^^^iPhone^^^

Lol silly iphone users

[NY07RS4]

Here is a snapshot of the diagnostic progression I experienced and the results after I noticed I was consuming oil and blowing large amounts of smoke out the tail pipes at certain times when driving.

Lots of smoke out the tailpipes when accelerating immediately following a stop at a light. Idle for roughly two minutes at the light after driving and then step on the gas when light turns green and puff, a good size plume of smoke. So it led me to believe it was a change in vacuum that was causing this. Positive pressure builds up then negative…then when it switched back to positive the smoke show would appear. Built up oil vapor with nowhere to go? I thought clogged PCV. (No smoke under WOT, no massive amounts of smoke during cold starts just a little blue puff for a second or two.)

1.) Went to the dealer. They swapped in a new PCV and cleaned the two PCV lines that lead to the vc’s. Problem was solved for 30 miles. Then it returned.

2.) Went back to the dealer. Performed compression test, removed I/M (it was full of oil) and replaced the PCV yet again. This time they also replaced the two PCV lines that lead to the vc’s. Problem was solved for 75 miles this time. Then it returned. I did my own compression test and the numbers were well within spec.

3.) Went back to the dealer. They literally repeated step 2 and gave me the car back. Only difference, I found a little check valve located under the I/M in a diagram during my research and iirc it actually routes bypass/oil vapor like residue directly into the I/M. It is not part of the PCV. The dealer yanked the I/M and replaced this part. Problem solved for 100 miles. Then it returned.

4.) Went back to the dealer. They did a leak down test and determined my valve seals were shot. Ordered new heads. Cleaned PCV, PCV lines and I/M. Installed new heads. Problem solved for ~300+ miles. Problem returned.

5.) Went back to dealer. They brought in a “specialist” and tore down the motor (removed heads etc) and performed additional “diagnostic procedures.” They discovered that every rod bearing was scored and that I had multiple egged pistons allowing massive amounts of oil to pass into the combustion chamber. Ordered the following parts: Short block, intake manifold, passenger side valve cover (new design) because you cannot get a vc gasket on that side without purchasing the cover (WTF), PCV, PCV lines, cam covers, multiple vacuum hoses, multiple coolant hoses and a slew of other odds and ends. Basically I ended up with a new engine top to bottom but it was piecemeal instead of a long block in one shot.

To give you an idea of how much oil I was going through…it was 1QT every 375 miles, no joke. I monitored this like crazy. The dealer also did their own oil consumption testing that matched up with my findings.

I may be leaving out some details since I’m doing this from memory and my notes are on another laptop. I did document most of this on this site in a thread so we can reference over there to compare to. I can also pull the invoices with the tech notes but they are horrible. Big block of text without any punctuation.

Hope this helps.

[NY07RS4]

Fuck you two and your Iphone jokes. ;D

[jason_addict]

LOL

[TypeRx]

Just another piece of “data” – my car had relatively equal amounts of carbon on both banks. Cleaned at 34.6K miles and never cleaned before that.

[koolade9]

Here is a snapshot of the diagnostic progression I experienced and the results after I noticed I was consuming oil and blowing large amounts of smoke out the tail pipes at certain times when driving.

Lots of smoke out the tailpipes when accelerating immediately following a stop at a light. Idle for roughly two minutes at the light after driving and then step on the gas when light turns green and puff, a good size plume of smoke. So it led me to believe it was a change in vacuum that was causing this. Positive pressure builds up then negative…then when it switched back to positive the smoke show would appear. Built up oil vapor with nowhere to go? I thought clogged PCV. (No smoke under WOT, no massive amounts of smoke during cold starts just a little blue puff for a second or two.)

1.) Went to the dealer. They swapped in a new PCV and cleaned the two PCV lines that lead to the vc’s. Problem was solved for 30 miles. Then it returned.

2.) Went back to the dealer. Performed compression test, removed I/M (it was full of oil) and replaced the PCV yet again. This time they also replaced the two PCV lines that lead to the vc’s. Problem was solved for 75 miles this time. Then it returned. I did my own compression test and the numbers were well within spec.

3.) Went back to the dealer. They literally repeated step 2 and gave me the car back. Only difference, I found a little check valve located under the I/M in a diagram during my research and iirc it actually routes bypass/oil vapor like residue directly into the I/M. It is not part of the PCV. The dealer yanked the I/M and replaced this part. Problem solved for 100 miles. Then it returned.

4.) Went back to the dealer. They did a leak down test and determined my valve seals were shot. Ordered new heads. Cleaned PCV, PCV lines and I/M. Installed new heads. Problem solved for ~300+ miles. Problem returned.

5.) Went back to dealer. They brought in a “specialist” and tore down the motor (removed heads etc) and performed additional “diagnostic procedures.” They discovered that every rod bearing was scored and that I had multiple egged pistons allowing massive amounts of oil to pass into the combustion chamber. Ordered the following parts: Short block, intake manifold, passenger side valve cover (new design) because you cannot get a vc gasket on that side without purchasing the cover (WTF), PCV, PCV lines, cam covers, multiple vacuum hoses, multiple coolant hoses and a slew of other odds and ends. Basically I ended up with a new engine top to bottom but it was piecemeal instead of a long block in one shot.

To give you an idea of how much oil I was going through…it was 1QT every 375 miles, no joke. I monitored this like crazy. The dealer also did their own oil consumption testing that matched up with my findings.

I may be leaving out some details since I’m doing this from memory and my notes are on another laptop. I did document most of this on this site in a thread so we can reference over there to compare to. I can also pull the invoices with the tech notes but they are horrible. Big block of text without any punctuation.

Hope this helps.

First off, thank you very much for posting this. It was indeed food for thought, and I’ve been chewing on it all weekend. Here’s my thoughts for the sake of discussion, and for trying to get to the bottom of this.

If the solution really was pistons out of round (or anything with the bottom end for that matter), then a few things don’t add up in my mind:

1. This would’ve shown up in a compression test…if your pistons/rings were so bad that they could blow-by oil, then they should certainly fail to compress air properly.

2. The fact that it went away temporarily after performing steps 1-4 doesn’t add up either. If it was really the bottom end, the problem should’ve come back immediately, regardless of the changes you made to the top end.

3. When they replaced the heads, did they replace the valve cover with the redesigned one? Or were they able to source a replacement gasket for the original one?

4. As a side note, the check valve underneath the IM is just that, a check valve for the vacuum lines at the front of the motor to keep the vacuum reservoir from going flat. If you can perform the airbox & IM flap actuation tests (output tests in vag-com), then this valve is working properly. There is a line that is used to drain the oil from the PCV back into the sump, but this doesn’t connect to the IM. After thinking about it for a second, if that line is clogged, it could cause problems with the PCV as well…I’ll investigate this…

5. How many miles were on the car during this whole process? Timeframe? (last year, two years ago, etc?)

Based on your info above, and after talking to Dan@jhm about his motor, I’m less convinced it’s the PCV, although it may be a part of the puzzle, and I’m now shifting my interest towards the valve cover on that side. It irks me that Audi would re-design that part after the model was out of production…why go through the trouble of changing that part design? I’m going to head to my dealer to see if he can dig up any information on when that part was released to get some idea of when that re-design took place and to see if that part is used on any other motors (Q7, RS5, etc…). if it’s not shared, I want to see if any of those valve covers underwent a redesign as well… I could be chasing nothing but a $600 waste of time, but if they didn’t change your valve cover when they replaced the heads, and my theory about the compression test is correct (meaning there really was nothing wrong with the bottom end), then the one variable that changed (with some bias, mind you) was the redesigned valve cover…

Anyone, please correct me where I could be wrong here… While a do find it a bit odd that a VC could cause that much of a problem, there was a reason it was redesigned…

Thoughts?

FWIW over half of the cars I’ve carbon cleaned have bank 2 wet compared to bank 1.

I can’t help but think this is another vote for a problem with the VC…Unless there is just some inherent difference in the design of the bank 1 head vs. bank 2…different valve seals or oil drain passages are all that would come mind, but I really think that’s a stretch.

Just another piece of “data” – my car had relatively equal amounts of carbon on both banks. Cleaned at 34.6K miles and never cleaned before that.

Just to clarify, I’m not referring to the CB itself, but actual wet oil (yet to be caked) on the valves in bank 2 vs. bank 1. The level of CB in both heads was about the same, with perhaps more in bank 2, but it’s a bit misleading with the extra oil on top of it.

[NY07RS4]

Here is a snapshot of the diagnostic progression I experienced and the results after I noticed I was consuming oil and blowing large amounts of smoke out the tail pipes at certain times when driving.

Lots of smoke out the tailpipes when accelerating immediately following a stop at a light. Idle for roughly two minutes at the light after driving and then step on the gas when light turns green and puff, a good size plume of smoke. So it led me to believe it was a change in vacuum that was causing this. Positive pressure builds up then negative…then when it switched back to positive the smoke show would appear. Built up oil vapor with nowhere to go? I thought clogged PCV. (No smoke under WOT, no massive amounts of smoke during cold starts just a little blue puff for a second or two.)

1.) Went to the dealer. They swapped in a new PCV and cleaned the two PCV lines that lead to the vc’s. Problem was solved for 30 miles. Then it returned.

2.) Went back to the dealer. Performed compression test, removed I/M (it was full of oil) and replaced the PCV yet again. This time they also replaced the two PCV lines that lead to the vc’s. Problem was solved for 75 miles this time. Then it returned. I did my own compression test and the numbers were well within spec.

3.) Went back to the dealer. They literally repeated step 2 and gave me the car back. Only difference, I found a little check valve located under the I/M in a diagram during my research and iirc it actually routes bypass/oil vapor like residue directly into the I/M. It is not part of the PCV. The dealer yanked the I/M and replaced this part. Problem solved for 100 miles. Then it returned.

4.) Went back to the dealer. They did a leak down test and determined my valve seals were shot. Ordered new heads. Cleaned PCV, PCV lines and I/M. Installed new heads. Problem solved for ~300+ miles. Problem returned.

5.) Went back to dealer. They brought in a “specialist” and tore down the motor (removed heads etc) and performed additional “diagnostic procedures.” They discovered that every rod bearing was scored and that I had multiple egged pistons allowing massive amounts of oil to pass into the combustion chamber. Ordered the following parts: Short block, intake manifold, passenger side valve cover (new design) because you cannot get a vc gasket on that side without purchasing the cover (WTF), PCV, PCV lines, cam covers, multiple vacuum hoses, multiple coolant hoses and a slew of other odds and ends. Basically I ended up with a new engine top to bottom but it was piecemeal instead of a long block in one shot.

To give you an idea of how much oil I was going through…it was 1QT every 375 miles, no joke. I monitored this like crazy. The dealer also did their own oil consumption testing that matched up with my findings.

I may be leaving out some details since I’m doing this from memory and my notes are on another laptop. I did document most of this on this site in a thread so we can reference over there to compare to. I can also pull the invoices with the tech notes but they are horrible. Big block of text without any punctuation.

Hope this helps.

First off, thank you very much for posting this. It was indeed food for thought, and I’ve been chewing on it all weekend. Here’s my thoughts for the sake of discussion, and for trying to get to the bottom of this.

Welcome.

If the solution really was pistons out of round (or anything with the bottom end for that matter), then a few things don’t add up in my mind:

1. This would’ve shown up in a compression test…if your pistons/rings were so bad that they could blow-by oil, then they should certainly fail to compress air properly.

I thought the same and inquired. The dealer was performing a compression test on a 2.0 motor during one of my visits that needed a ring job. SM walked me over to the tech who doing the test. Showed me the readout and report. It was low but within spec. (BTW, both tests, mine and th dealer were both DRY tests.)

2. The fact that it went away temporarily after performing steps 1-4 doesn’t add up either. If it was really the bottom end, the problem should’ve come back immediately, regardless of the changes you made to the top end.

It was concluded as follows: it cleaned up all of the excess that had accumulated that was burning up and causing large plumes of dark smoke. When it’s spic and span the blow by/oil seepage still passed through but was a light enough volume that it burned up quickly and I didn’t notice the plumes of smoke as readily because they were more faint. When it accumulated over 50-100 miles of driving it was again thick from accumulation and started to really show by plumes and plumes during the situations I described above. Keep in mind this issue was more than likely a combination of a couple of failing or failed items. I’m sure the valves were leaking but the egged pistons were the largest contributor. The showed me all of the measurements, how they measured each component, the scored rods etc. They had to prove every last bit to the warranty company and the AoA peopl who got involved. This wasn’t a magic wand response to keep me satisfied or quiet or anything else.

3. When they replaced the heads, did they replace the valve cover with the redesigned one? Or were they able to source a replacement gasket for the original one?

Replaced it with the revised one.

4. As a side note, the check valve underneath the IM is just that, a check valve for the vacuum lines at the front of the motor to keep the vacuum reservoir from going flat. If you can perform the airbox & IM flap actuation tests (output tests in vag-com), then this valve is working properly. There is a line that is used to drain the oil from the PCV back into the sump, but this doesn’t connect to the IM. After thinking about it for a second, if that line is clogged, it could cause problems with the PCV as well…I’ll investigate this…

I may have stated this incorrectly, it was not a vacuum line. It was part of the oil recirc path. Towards the back of the block and didn’t look to connect to the PCV. It also looks like it is vertical shooting directly into the I/M. I will look to see if I can find the diagram I brought to show the dealer.

5. How many miles were on the car during this whole process? Timeframe? (last year, two years ago, etc?)

59,000/ 09/11 first visit to the dealer to discuss issue.
63,725/ 02/12 New short block, problem 100% solved

Based on your info above, and after talking to Dan@jhm about his motor, I’m less convinced it’s the PCV, although it may be a part of the puzzle, and I’m now shifting my interest towards the valve cover on that side. It irks me that Audi would re-design that part after the model was out of production…why go through the trouble of changing that part design? I’m going to head to my dealer to see if he can dig up any information on when that part was released to get some idea of when that re-design took place and to see if that part is used on any other motors (Q7, RS5, etc…). if it’s not shared, I want to see if any of those valve covers underwent a redesign as well… I could be chasing nothing but a $600 waste of time, but if they didn’t change your valve cover when they replaced the heads, and my theory about the compression test is correct (meaning there really was nothing wrong with the bottom end), then the one variable that changed (with some bias, mind you) was the redesigned valve cover…

Anyone, please correct me where I could be wrong here… While a do find it a bit odd that a VC could cause that much of a problem, there was a reason it was redesigned…

Thoughts?

FWIW over half of the cars I’ve carbon cleaned have bank 2 wet compared to bank 1.

I can’t help but think this is another vote for a problem with the VC…Unless there is just some inherent difference in the design of the bank 1 head vs. bank 2…different valve seals or oil drain passages are all that would come mind, but I really think that’s a stretch.

Just another piece of “data” – my car had relatively equal amounts of carbon on both banks. Cleaned at 34.6K miles and never cleaned before that.

Just to clarify, I’m not referring to the CB itself, but actual wet oil (yet to be caked) on the valves in bank 2 vs. bank 1. The level of CB in both heads was about the same, with perhaps more in bank 2, but it’s a bit misleading with the extra oil on top of it.

[sakimano]

Would love to talk to audi or quattro to find out why this part change was made

Try posting some of this on Rs246 koolade9. There are more rs4 board members there in the uk than all other forums combined. They’ve already discussed this part change there.

It feels like you’re on the verge of solving a big mystery, personally.

[koolade9]

1. This would’ve shown up in a compression test…if your pistons/rings were so bad that they could blow-by oil, then they should certainly fail to compress air properly.

I thought the same and inquired. The dealer was performing a compression test on a 2.0 motor during one of my visits that needed a ring job. SM walked me over to the tech who doing the test. Showed me the readout and report. It was low but within spec. (BTW, both tests, mine and th dealer were both DRY tests.)

2. The fact that it went away temporarily after performing steps 1-4 doesn’t add up either. If it was really the bottom end, the problem should’ve come back immediately, regardless of the changes you made to the top end.

It was concluded as follows: it cleaned up all of the excess that had accumulated that was burning up and causing large plumes of dark smoke. When it’s spic and span the blow by/oil seepage still passed through but was a light enough volume that it burned up quickly and I didn’t notice the plumes of smoke as readily because they were more faint. When it accumulated over 50-100 miles of driving it was again thick from accumulation and started to really show by plumes and plumes during the situations I described above. Keep in mind this issue was more than likely a combination of a couple of failing or failed items. I’m sure the valves were leaking but the egged pistons were the largest contributor. The showed me all of the measurements, how they measured each component, the scored rods etc. They had to prove every last bit to the warranty company and the AoA peopl who got involved. This wasn’t a magic wand response to keep me satisfied or quiet or anything else.

3. When they replaced the heads, did they replace the valve cover with the redesigned one? Or were they able to source a replacement gasket for the original one?

Replaced it with the revised one.

4. As a side note, the check valve underneath the IM is just that, a check valve for the vacuum lines at the front of the motor to keep the vacuum reservoir from going flat. If you can perform the airbox & IM flap actuation tests (output tests in vag-com), then this valve is working properly. There is a line that is used to drain the oil from the PCV back into the sump, but this doesn’t connect to the IM. After thinking about it for a second, if that line is clogged, it could cause problems with the PCV as well…I’ll investigate this…

I may have stated this incorrectly, it was not a vacuum line. It was part of the oil recirc path. Towards the back of the block and didn’t look to connect to the PCV. It also looks like it is vertical shooting directly into the I/M. I will look to see if I can find the diagram I brought to show the dealer.

5. How many miles were on the car during this whole process? Timeframe? (last year, two years ago, etc?)

59,000/ 09/11 first visit to the dealer to discuss issue.
63,725/ 02/12 New short block, problem 100% solved

Thanks for the info… I need to measure my oil consumption. I don’t think I’m at near as much as you were, but then again, I haven’t driven the car much in the last 4 months. I’m with you in thinking it’s a combination of things. My hope is that it hasn’t progressed to the bottom end and I can solve this without cracking the heads… I’d be lying if I said your post wasn’t discouraging though…I was really hoping the VC was going to be the deciding factor.

Would love to talk to audi or quattro to find out why this part change was made

Try posting some of this on Rs246 koolade9. There are more rs4 board members there in the uk than all other forums combined. They’ve already discussed this part change there.

It feels like you’re on the verge of solving a big mystery, personally.

Good call on 246… I’m searching through there now to see what those guys have done.

When I called my parts guy today, he said they changed that part in January of '09, and he also showed a change on the R8 from '08 to '09… Makes sense, as they still produce the BNS. Probably the same cover with a different finish…?

I really hope your premonition is correct…

[sakimano]

What do they produce our engine for now? Or do you just mean for replacement stock/parts rules?

[koolade9]

What do they produce our engine for now? Or do you just mean for replacement stock/parts rules?

I meant for the R8 V8 (2008-10)…they stopped producing our variant, but the R8 continued…that would negate the redesign as the motor would continue on after the RS4 went away. I’m guessing we really do have the same valve covers, the RS just has a different surface finish. This is unverified of course, just an educated guess…

[sakimano]

The R8 changed over to the RS5 engine which is quite different didn’t it? Still there should be enough information out there.

Reil went out of his way to say the RS4/5 (B8) engine was almost entirely different to the previous one. Could be to address concerns that they’re sitting on their laurels and using an engine that debuted in 2005 nearly 7 years later on the new cars…but it could also be to let people know they’ve addressed a couple of the recurring problems.

[koolade9]

The R8 changed over to the RS5 engine which is quite different didn’t it? Still there should be enough information out there.

It did (in 2011 or 2010)…I edited my post to be more clear, I was referring to the 2006-2010 version, which was our BNS + dry sump.

[quote=“sakimano,post:18,topic:4118”]
Its marketing hype…how else would you pump up the engine that made the R8 grossly underpowered, was already used in their saloon car, yet it’s okay for the coupe? :-\ To relate that to the topic at hand, I’m guessing the valve covers on the RS5, (B8) RS4, and new R8 are different from ours…if not in function, then certainly in form…

[koolade9]

Revised valve cover & new PCV ordered. I’ve already picked up the other VC gasket but will do them both at the same time…

My smoking issue isn’t consistent…I’ve had a couple days with 50-60 mile drives and no smoking issues. I did see it a couple times this morning though. It just doesn’t seem consistent enough to point to the bottom end IMO…at least in my situation…

Troubleshooting process:
-replace VC gaskets & updated VC, inspect old covers for potential issues. Will report findings.
-if no effect, improvise a catch-can setup to essentially remove any potential restriction from the crank case.
-if no effect, we’re looking at a valve seal and/or piston issue, as I’m out of ideas at that point.

I’m hopeful the first two steps yield results.