use to have 626 when a joined this forum while back...now driving 2001 Audi S4..you should do something similar to what saaber1 did
FSI Engines - Audi RS4 Engine Oil-Related Deposits
- Thread starter RI_RS4
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What did saaber1 do? Any chance someone could do a How To writeup that included the material one needs?
Also, zoomzoom, I just bought an expensive complete Oil Catch Can kit. It uses two PCV's and is supposed to be really good. Will this help significantly or just be a mediocre fix that just delays the inevitable?
I really want to do what you did, vent to atmosphere. In my state, we don't have emission inspections at all, so it's not a concern. And like you said, in reality, I'm actually saving the environment when you consider what these buildups cause. I just need a list of materials and a How To article to do it, as most of this is over my head.
Also, zoomzoom, I just bought an expensive complete Oil Catch Can kit. It uses two PCV's and is supposed to be really good. Will this help significantly or just be a mediocre fix that just delays the inevitable?
I really want to do what you did, vent to atmosphere. In my state, we don't have emission inspections at all, so it's not a concern. And like you said, in reality, I'm actually saving the environment when you consider what these buildups cause. I just need a list of materials and a How To article to do it, as most of this is over my head.
Originally Posted By: RI_RS4
I've been posting on Audi FSI engines for some time now, and have discussed my oil analysis and issues with FSI engine fuel dilution impact on wear and deposit formation. Well, we now have confirmation of the oil-induced deposit formation issues with FSI engines.
Here's a direct quote from an RS4 owner who is also a Mechanical Engineer.
Quote:
A little over a month ago, had the car in for CEL, misfires, etc. They found bad injectors, replaced them and the car runs fine now. They also found the buildup on the intake valves that been talked about here. I was able to briefly look at it while they were cleaning them, but wasn't really able to inspect them. Well, I took the manifold off myself this weekend because I was bored and felt like wrenching on my car. It obvious from the intake ports and intake manifold that there is quite a bit of oil vapor in the intake air stream. Which is typical, especially on high performance engines. There is a light oily film on the manifold port (and flaps) leading directly into the cylinder head as well as in the port itself. The closer you get to the valves, the film is more tacky and in some places, almost hard. But not like dry flakes. IMO, the oil vapor entrained in the air stream just clings to the valves and sticks because the valves are relatively hot. Its not "carbon" buildup due to combustion, its oil film buildup thats not effectively cleaned by fuel since the engine is direct injected, not port injected. The RS4 has an elaborate crankcase ventilation system equipped with a 3-stage venturi cyclone to help remove the oil particles. Obviously it doesn't separate all the oil out. I don't think some buildup would be out of the ordinary on these engines. The valve in the pic was the worst and its been roughly 800 miles since the dealer cleaned them.
Quote:
After my $70k car's performance went down the gutter (the first oil change after the break in), I dug into it. I do various data logs almost every day. I plot the info and try to notice certain trends. After a while, things become clear but after you see your intake valves crudded up beyond belief and then in bad shape again only 800 miles later, it becomes obvious. The volatized oil creates buildup, which constantly breaks apart, which enters the combustion chamber, then adheres to injectors, which disrupts flow patterns and/or causes injector damage, which leads to poor economy and performance and fuel leakage into the chamber, that leads to cold start misfires and damaged coils. The buildup also drastically affects airflow into the engine. Dealers are good at replacing the coils, but bad at persisting to find what the root cause is. Its so ironic that the RS4 community thinks that my car is an exception just because I took the time to unveil an obvious problem. I would bet that 80% of them are having the same issues. Its really a shame, because the 4.2 FSI is going to get a bad wrap when its truly a masterpiece. I ordered 5gal of the RLI 5W40 and will be monitoring the intake valve buildup since I have no problem taking my manifold off to see what's going on.
IMO fuel dilution is the root cause for increased volatization and breakdown of the oil. 10 year oil Audi/VW formulations, designed to deal with engine sludge, do not stand up to fuel breakdown and end up as deposits on the valves, combustion chamber and injectors.
I disagree with the theory that the blow by from the PCV system is the cause of the severe intake port and valve deposits occurring in T/FSI Audi engines. (VWs too.) I don't believe the volume of the suspended lube oil and fuel aerosols in the crankcase ventilation is high enough to result in the amount of deposits typically found, that develop with low running time hours/miles.
Much more likely, the deposits are caused by the internal EGR. To provide for the Internal EGR, the VVT is used to extend the overlap in the valve timing a lot, with a variable percentage of effective EGR based on several factors, controlled by the ECU.
This is provoked by the absence of port fuel injection on the FSIs that on earlier manifold port fuel injection systems, washes the deposits off of the port walls and valves.
The high valve overlap angles, causes the exhaust gasses in the cylinder, to be blown into the intake ports, then the flow reverses and the exhaust gas and fresh air enter the cylinder as the intake stroke commences further. Therefore, the vaporized fuel heavy ends that are in the recirculated exhaust, has two passes past the much cooler intake ports and the valve heads where the vaporized fractions condense and build up on the effected parts. The same process occurs in the manifold port injection Audi engines that incorporate the VVT to provide the Internal EGR function, but also have the fuel washing the deposits away in the manifold injection engines.
I've been posting on Audi FSI engines for some time now, and have discussed my oil analysis and issues with FSI engine fuel dilution impact on wear and deposit formation. Well, we now have confirmation of the oil-induced deposit formation issues with FSI engines.
Here's a direct quote from an RS4 owner who is also a Mechanical Engineer.
Quote:
A little over a month ago, had the car in for CEL, misfires, etc. They found bad injectors, replaced them and the car runs fine now. They also found the buildup on the intake valves that been talked about here. I was able to briefly look at it while they were cleaning them, but wasn't really able to inspect them. Well, I took the manifold off myself this weekend because I was bored and felt like wrenching on my car. It obvious from the intake ports and intake manifold that there is quite a bit of oil vapor in the intake air stream. Which is typical, especially on high performance engines. There is a light oily film on the manifold port (and flaps) leading directly into the cylinder head as well as in the port itself. The closer you get to the valves, the film is more tacky and in some places, almost hard. But not like dry flakes. IMO, the oil vapor entrained in the air stream just clings to the valves and sticks because the valves are relatively hot. Its not "carbon" buildup due to combustion, its oil film buildup thats not effectively cleaned by fuel since the engine is direct injected, not port injected. The RS4 has an elaborate crankcase ventilation system equipped with a 3-stage venturi cyclone to help remove the oil particles. Obviously it doesn't separate all the oil out. I don't think some buildup would be out of the ordinary on these engines. The valve in the pic was the worst and its been roughly 800 miles since the dealer cleaned them.
Quote:
After my $70k car's performance went down the gutter (the first oil change after the break in), I dug into it. I do various data logs almost every day. I plot the info and try to notice certain trends. After a while, things become clear but after you see your intake valves crudded up beyond belief and then in bad shape again only 800 miles later, it becomes obvious. The volatized oil creates buildup, which constantly breaks apart, which enters the combustion chamber, then adheres to injectors, which disrupts flow patterns and/or causes injector damage, which leads to poor economy and performance and fuel leakage into the chamber, that leads to cold start misfires and damaged coils. The buildup also drastically affects airflow into the engine. Dealers are good at replacing the coils, but bad at persisting to find what the root cause is. Its so ironic that the RS4 community thinks that my car is an exception just because I took the time to unveil an obvious problem. I would bet that 80% of them are having the same issues. Its really a shame, because the 4.2 FSI is going to get a bad wrap when its truly a masterpiece. I ordered 5gal of the RLI 5W40 and will be monitoring the intake valve buildup since I have no problem taking my manifold off to see what's going on.
IMO fuel dilution is the root cause for increased volatization and breakdown of the oil. 10 year oil Audi/VW formulations, designed to deal with engine sludge, do not stand up to fuel breakdown and end up as deposits on the valves, combustion chamber and injectors.
I disagree with the theory that the blow by from the PCV system is the cause of the severe intake port and valve deposits occurring in T/FSI Audi engines. (VWs too.) I don't believe the volume of the suspended lube oil and fuel aerosols in the crankcase ventilation is high enough to result in the amount of deposits typically found, that develop with low running time hours/miles.
Much more likely, the deposits are caused by the internal EGR. To provide for the Internal EGR, the VVT is used to extend the overlap in the valve timing a lot, with a variable percentage of effective EGR based on several factors, controlled by the ECU.
This is provoked by the absence of port fuel injection on the FSIs that on earlier manifold port fuel injection systems, washes the deposits off of the port walls and valves.
The high valve overlap angles, causes the exhaust gasses in the cylinder, to be blown into the intake ports, then the flow reverses and the exhaust gas and fresh air enter the cylinder as the intake stroke commences further. Therefore, the vaporized fuel heavy ends that are in the recirculated exhaust, has two passes past the much cooler intake ports and the valve heads where the vaporized fractions condense and build up on the effected parts. The same process occurs in the manifold port injection Audi engines that incorporate the VVT to provide the Internal EGR function, but also have the fuel washing the deposits away in the manifold injection engines.
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Originally Posted By: diagnosticator1
I disagree with the theory that the blow by from the PCV system is the cause of the severe intake port and valve deposits
Yea, the literally GALLONS of pcv gunk collected by catch cans which normally go right onto the intake valves have nothing to do with the problem.... (shakes head)
I have run my car on purpose with it venting to the atmosphere and you get oily gunk coming out like crazy. The PCV system dumps loads of gunk onto the valves. Please read about the issue more.
I disagree with the theory that the blow by from the PCV system is the cause of the severe intake port and valve deposits
Yea, the literally GALLONS of pcv gunk collected by catch cans which normally go right onto the intake valves have nothing to do with the problem.... (shakes head)
I have run my car on purpose with it venting to the atmosphere and you get oily gunk coming out like crazy. The PCV system dumps loads of gunk onto the valves. Please read about the issue more.
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I'd bet the problem is from both PCV vapors and EGR. How much each contributes is the big unknown to me; I'm sure the answer is that "it depends". All of the pics I've seen of valve buildup show it to be jet black, indicating high free carbon content which points to EGR, IMO. It doesn't take much free carbon mixed with other stuff for the mixture to look jet black, so this does not rule out PCV vapor contribution.
saaber1, as you know, you are in a unique position to determine how much contribution EGR has since you've eliminated the PCV source. But I know it is inconvenient to view the valves. Does your re-routing eliminate PCV vapors under both boost and vacuum conditions?
saaber1, as you know, you are in a unique position to determine how much contribution EGR has since you've eliminated the PCV source. But I know it is inconvenient to view the valves. Does your re-routing eliminate PCV vapors under both boost and vacuum conditions?
If my hypothesis is accurate, then the "pools" of oil in the intake manifold are irrelevant to the deposit accumulation.
Yes, I agree with you on the blow by having at lease a partial share in causing the deposits, and the effective amount of the total is determined by and varies with operating conditions, that are different for each case.
In addition, since the lube oil has a lot of detergents and TBN modifiers, I don't think the hard carbon deposits will result from that chemistry even if it's a significant part of the total, compared to the EGR fractions.
Originally Posted By: diagnosticator1
In addition, since the lube oil has a lot of detergents and TBN modifiers, I don't think the hard carbon deposits will result from that chemistry even if it's a significant part of the total, compared to the EGR fractions.
Well, there is the guy that had massive deposits formed, had them cleaned, then switched oils to RLI (I think it was them) and later took it off again and he didn't have deposits, just a tacky residue that wasn't really too bad. That in itself is proof to me.
I don't have the link anymore, another forum. But I read it from one of the links saaber had.
In addition, since the lube oil has a lot of detergents and TBN modifiers, I don't think the hard carbon deposits will result from that chemistry even if it's a significant part of the total, compared to the EGR fractions.
Well, there is the guy that had massive deposits formed, had them cleaned, then switched oils to RLI (I think it was them) and later took it off again and he didn't have deposits, just a tacky residue that wasn't really too bad. That in itself is proof to me.
I don't have the link anymore, another forum. But I read it from one of the links saaber had.
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Hello, I recently joined the forum, after reading occasionally over the years. I've started paying particular attention to the DI engines, especially Audi's, as I have a 2010 S5 on order with the 4.2 FSI V8 engine.
I didn't see this discussed in this thread or other Audi DI threads, so if I overlooked it please excuse me. I came across this article from Lubrizol, presented at a 2006 conference: http://www.lubrizol.com/EuropeanEngineOils/UEIL2006LowerSAPS.html it's titled "Lower SAPS Engine Oils:
Essential components in maintaining vehicle emissions compliance", and it's interesting reading, especially when you get to page 19.
They claim testing has proven that Euro 4 lower SAPS oils are significantly better in preventing valve deposits in direct injection gasoline engines, in comparison to OEM-approved Euro 3 engine oils.
Can prevention or reduction of valve deposits really be that simple? There may be much to this, if rli-rs4's data compilation has shown the RLI Biosyn to show a significant improvement. Thoughts, please? What are the Audi-approved Euro 4 low SAP oils out there?
I didn't see this discussed in this thread or other Audi DI threads, so if I overlooked it please excuse me. I came across this article from Lubrizol, presented at a 2006 conference: http://www.lubrizol.com/EuropeanEngineOils/UEIL2006LowerSAPS.html it's titled "Lower SAPS Engine Oils:
Essential components in maintaining vehicle emissions compliance", and it's interesting reading, especially when you get to page 19.
They claim testing has proven that Euro 4 lower SAPS oils are significantly better in preventing valve deposits in direct injection gasoline engines, in comparison to OEM-approved Euro 3 engine oils.
Can prevention or reduction of valve deposits really be that simple? There may be much to this, if rli-rs4's data compilation has shown the RLI Biosyn to show a significant improvement. Thoughts, please? What are the Audi-approved Euro 4 low SAP oils out there?
Originally Posted By: GordonC
They claim testing has proven that Euro 4 lower SAPS oils are significantly better in preventing valve deposits in direct injection gasoline engines, in comparison to OEM-approved Euro 3 engine oils.
Can prevention or reduction of valve deposits really be that simple? There may be much to this, if rli-rs4's data compilation has shown the RLI Biosyn to show a significant improvement. Thoughts, please? What are the Audi-approved Euro 4 low SAP oils out there?
Welcome GordonC, and thanks for the info. You can pick up Castrol SLX III at all VW/Audi dealers. It's a 504/507 oil.
They claim testing has proven that Euro 4 lower SAPS oils are significantly better in preventing valve deposits in direct injection gasoline engines, in comparison to OEM-approved Euro 3 engine oils.
Can prevention or reduction of valve deposits really be that simple? There may be much to this, if rli-rs4's data compilation has shown the RLI Biosyn to show a significant improvement. Thoughts, please? What are the Audi-approved Euro 4 low SAP oils out there?
Welcome GordonC, and thanks for the info. You can pick up Castrol SLX III at all VW/Audi dealers. It's a 504/507 oil.
Here's something I found from another site -- seems like the BG company is planning to take advantage of this problem and turn it into a cash cow!!
Regards,
paul...
http://www.bgfueltest.com/
Regards,
paul...
http://www.bgfueltest.com/
Originally Posted By: GordonC
They claim testing has proven that Euro 4 lower SAPS oils are significantly better in preventing valve deposits in direct injection gasoline engines, in comparison to OEM-approved Euro 3 engine oils.
Can prevention or reduction of valve deposits really be that simple? There may be much to this, if rli-rs4's data compilation has shown the RLI Biosyn to show a significant improvement. Thoughts, please? What are the Audi-approved Euro 4 low SAP oils out there?
I have a 2007 Audi A6 Quattro, and its very tough on oil. At 51K miles, The engine was sludged up, despite running Total ineo MC3 low SAP. The only thing I can tell you to do with these engines, is to throw in lubromoly motor clean every other oil change. Let it run in there for 10 minutes, and then drain the oil. This is the only way I've found to reduce the sludge.
They claim testing has proven that Euro 4 lower SAPS oils are significantly better in preventing valve deposits in direct injection gasoline engines, in comparison to OEM-approved Euro 3 engine oils.
Can prevention or reduction of valve deposits really be that simple? There may be much to this, if rli-rs4's data compilation has shown the RLI Biosyn to show a significant improvement. Thoughts, please? What are the Audi-approved Euro 4 low SAP oils out there?
I have a 2007 Audi A6 Quattro, and its very tough on oil. At 51K miles, The engine was sludged up, despite running Total ineo MC3 low SAP. The only thing I can tell you to do with these engines, is to throw in lubromoly motor clean every other oil change. Let it run in there for 10 minutes, and then drain the oil. This is the only way I've found to reduce the sludge.
How come the oil specified for the RS4 in the US is 5W-40 (502) and the rest of the world it looks like a 5W-30 (504/7) oil is specified.
I read the 504/7 specification superceded 502.. so is it OK to use a 5W-30 in the US? Would I be causing any increased wear etc?
Thanks folks!
I read the 504/7 specification superceded 502.. so is it OK to use a 5W-30 in the US? Would I be causing any increased wear etc?
Thanks folks!
Originally Posted By: rs4vr
How come the oil specified for the RS4 in the US is 5W-40 (502) and the rest of the world it looks like a 5W-30 (504/7) oil is specified.
I read the 504/7 specification superceded 502.. so is it OK to use a 5W-30 in the US? Would I be causing any increased wear etc?
Thanks folks!
I'm going to guess one or several of these:
- We are still on the fixed-interval of 10K miles (whereas 504.00/507.00 is a long drain oil)
- Our fuel may not be up to the same standards (causing issues with BMW)
- Fuel management may be different (lean-burn not included due to US emissions)
Anyone else have thoughts about this?
How come the oil specified for the RS4 in the US is 5W-40 (502) and the rest of the world it looks like a 5W-30 (504/7) oil is specified.
I read the 504/7 specification superceded 502.. so is it OK to use a 5W-30 in the US? Would I be causing any increased wear etc?
Thanks folks!
I'm going to guess one or several of these:
- We are still on the fixed-interval of 10K miles (whereas 504.00/507.00 is a long drain oil)
- Our fuel may not be up to the same standards (causing issues with BMW)
- Fuel management may be different (lean-burn not included due to US emissions)
Anyone else have thoughts about this?
I did read that US gasoline tends to have higher levels of sulfur and ethanol.
I'm wondering if this is part of the issue.
I'm wondering if this is part of the issue.
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