Fuel adatives....

[P_G]

The carbon build up is an Audi known effect of FSI technology however is not a known engine issue. What has been suggested to me is that RS4's that are used for short commutes and stop start driving or those with low usage, i.e. weekend toys or occasional usage will accumulate carbon build up more than those that are thrashed like they are supposed to. Also, FSI engines like a good long motorway run which will lessen the build up to a degree.

I may also try the Wynn's stuff, taking manifolds off and cleaning is a great idea but when it is my daily commute it is not feasible. Pippyrips, I'd be interested to know how you get on once you have used it.

[pippyrips]

The carbon build up is an Audi known effect of FSI technology however is not a known engine issue. What has been suggested to me is that RS4's that are used for short commutes and stop start driving or those with low usage, i.e. weekend toys or occasional usage will accumulate carbon build up more than those that are thrashed like they are supposed to. Also, FSI engines like a good long motorway run which will lessen the build up to a degree.

I may also try the Wynn's stuff, taking manifolds off and cleaning is a great idea but when it is my daily commute it is not feasible. Pippyrips, I'd be interested to know how you get on once you have used it.

I think the carbon and oil, gum like deposits on the valves are 2 differnet things.

PG - i don't on using my Wynn's for a while yet as tempting as it is.

My valves/vains etc are going to be cleaned while the manifold is off and i want to the condition inside the engine without an prior cleaning.

No matter how good this Wynns product is, i can't see it shifting the type of buildup we have seen in this thread. I am hopful though it will avoid it building up again once the engine is cleaned up properly.

Is it just me or is anyone else p*ssed off with Audi at the moment

[RI_RS4]

Is it just me or is anyone else p*ssed off with Audi at the moment

Well yeppers! I wrote the following to Audi management in 2007:

Date: 1/13/2007
To: Marc.Trahan@audi.com

Marc Trahan
Director, Product Quality and Technical Service
Audi of America, Inc.


Dear Marc,


I am seeing an oil fuel dilution issue with the RS4 4.2L FSI V8 engine, which is significantly affecting oil life and lubrication efficiency. Dealer service technicians are not really prepared to deal with an issue like this, which is why I am contacting you directly. However, it's ramifications are significant. I currently have an 11,000 mile oil analysis record for the RS4 which quite conclusively shows that 1.5% to 2% fuel dilution is typical, is causing a reduction in oil life, and increased engine wear. This has been validated across multiple vehicles, with multiple 502.00 approved oils, and is quite consistent. Fuel dilution of engine oil seems to be a consequence of the FSI direct injection system, and may be exacerbated by the removal of stratified charge mode in the US. Additionally, my tests have shown that the problem exists regardless of the driving style and average torque output of the engine over the driving cycle. As a result, I have enlisted the services of a tribologist to further study the problem and suggest potential lubrication and fuel additive solutions.

I'm sure that Audi engineering must be aware of this situation and it's impact on the potential for 10K mile OCI in the US, and extended OCI in Europe. Are there any specific corrective measures or recommendations that are being provided by the engineers in Germany?

Unless the issue is specifically related to an RS4 engine design issue, which is doubtful, I would expect that oil fuel dilution issues exist for all variants of the 4.2L FSI engine family in the A6, A8, Q7, R8 and RS4 lines. However, due to the high-revving nature of the RS4 engine (and the R8), there is an additional potential for fuel diluted oil to cause increased bearing cavitation wear, catastrophic failure of bearing surfaces, and excessive intake valve deposits. At this point, I am doing what I can to mitigate the risks with my engine, however, I would like Audi of America to address this serious problem, and provide known solutions.

I will welcome any help you can provide in expediting this matter.


Regards,

Scott

I did not receive an Email response, so on 1/18/2007 I sent this:

Marc

Since I have not received a reply or acknowledgment to my previous email of February 13, 2007, I will be forwarding a letter to your office by registered mail. Expect to receive it early next week.

I will look forward to your reply.

regards,

Scott

Then I realized that the date I stated was wrong, so I sent this again on the 18th:

Mark,

The date I referenced below should have been January 13, 2007, not February 13, 2007. I was getting ahead of myself. I apologize for the confusion.

Scott

Finally, he responded with this:

From: Marc.Trahan@audi.com
Date: 2/1/2007 2:14 PM

Scott,

Attached is the statement I have from our engine development group. I have also spoke with two of the key mangers in the group, and they assure me that 2% dilution is quite normal and presents no problem.

Regards,

Marc Trahan
Director, Product Quality and Technical Service

Audi of America, Inc.
3800 Hamlin Road
Auburn Hills, MI. 48326
Unites States of America
Tel. +1 248 754 4885
Fax. +1 248 754 5150
mailto:marc.trahan@audi.com
http:www.audiusa.com

How fuel gets into engine oil
- Non-volatile parts of fuel in Blowby gas condense in crank case
- During cold start, fuel condenses at cylinder wall and will be transportet
from the piston rings into the oil pan and thereby into the oil

Oil Dilution in V8/V10 FSI engines from Audi
- Oil Dilution up to 3% ist absolutely normal and cause no problems at all
- In case of higher rate of short distance driving, oil dilution can go up to 5%;
this would cause in the long term wear, especially at chain drive and cylinder wall,
but which is still acceptable
- Permanent short distance driving, frequent cold starts, overrunned OCI´s or problems
in the fuel injection system can cause oil dilution which is significantly higher than
5%. This can be recognized at the oil dipstick, when oil level stays constant or increases.
This will cause high wear in engine components.

What Audi does to prevent oil dilution
- All V8/V10 FSI engine has got a "Positive Crankcase Ventilation system" in order to
transport fuel as well as water steam out of the oil as soon as possible
- All V8/V10 FSI engines have got a water cooled oil cooler, which heats up the oil
during warm-up phase of engine. Due to that, fuel in oil can evaporate very fast.

I then responded with the following:

Marc,

Thank you and the Audi Engineering team for taking the time to respond to my email. I will, however, note, for the record, that some of my questions have not been answered satisfactorily. My measurement data rules out the cold start hypothesis as root cause for this problem, indicating that another mechanism is at work As such, I will continue to monitor and document this problem over the life of the engine, as this level of oil fuel dilution is having disastrous impact on the oil, causing viscosity shear and extreme flashpoint reduction. Additionally, since Audi Engineering has not provided a metric for "normal" vs. "high" wear, I would appreciate a clarification of these terms based on known tribological measurement methods, so that the terms being used have a reasonable frame of reference for future discussion.

Regards,

Scott

I received no reply, so on the 23rd I sent this:

Marc,

I have not received a response to this request for more information from Audi of America. I am concerned that you are not taking this problem seriously. A recent used oil analysis of mine showed a flash point reduction from 420F down to 235F, in 502 oil that had been in service for less than 3000 miles. I also have a record of similar problems with other 420 HP 4.2L FSI V8 engines. Unfortunately, your previous explanation is incomplete, and provides little guidance for owners.

Again, I respectfully request that Audi of America provide a metric by which "acceptable" or "normal" wear can be differentiated from "high wear", utilizing commonly known and accepted tribological practices. Additionally, since Audi is requiring that all owners use oil that meets the Audi/VW 502.00 oil quality standard, I will request that a copy of that full standard be provided for my review.

Regards,

Scott

He finally responded on March 9th with this:

From: Marc.Trahan@audi.com
Date: 3/9/2007 8:52 AM

Scott,

Here a statement that we have received form our oil supplier Castrol.


*
Depending on the amount of fuel which is in the oil, viscosity of oil will be reduced
*
New oil has got a viscosity from about 14-15 mm²/s; with a fuel dilution from about
10%, this viscosity is reduced about 25% down to 11 mm²/s.
*
Normally this is not a serious problem because fuel can - and will - evaporate when oil temperature
is permanently high enough (more than 80°C)
*
BUT: Not every part of the fuel can evaporate completely. This behaviour depends especially from
the fuel quality. "Bad" fuel has got a high rate of non-volatile parts which will never evaporate.
*
Unfortunately, such "bad" fuel you can mostly find in China or: USA
*
Worst-Case is than thick, tough, black oil sludge. If oil reaches this stadium, oil is "destroyed"
and can´t lubricate the engine any more. This is the point that can cause dangerous engine
wear.
*
In addition to these facts, fuel dilution can cause other problems in the engine, e.g. demolition
of all seals which have contact with the fuel in oil. They will swell and then they get porous.

At that point I let the discussion go, since I'd placed Audi officially on notice about the problems with FSI fuel dilution and valve deposits. In January, when problems started surfacing on Audi forums, I shot this email off to Marc:

Date: 1/5/2009 8:09 PM
Marc.Trahan@audi.com

Marc

Does AoA currently have a technical understanding of the root cause of the current intake valve deposit problems in FSI engines? I understand that this is a service problem across many of the engine lines, and specifically has been a problem with the high performance V8.

regards,

Scott

[RI_RS4]

I intended the previous email exchange to provide documentation of a future class action law suit, should it ever be necessary. In conjunction with this, I maintain a database of over 100 oil analysis samples, on 21 RS4 engines, that were performed at the same ISO certified measurement laboratory, and interpreted by a professional Tribologist, with over 30 years industry consulting experience.

[pippyrips]

RI_RS4 - dobyou have a view on the performance of Fuchs Titan GT1 oil?

[SR71]

This is getting interesting.

In the meantime 5K miles is the absolute maximum my Titan Fuchs is going to see in my car.

It is yet another reason why cars might not be producing 414bhp - because they're only flowing 90% of the air they should.

- Permanent short distance driving, frequent cold starts, overrunned OCI´s or problems
in the fuel injection system can cause oil dilution which is significantly higher than
5%. This can be recognized at the oil dipstick, when oil level stays constant or increases.
This will cause high wear in engine components.

I like that bit most.

All you guys who think your car isn't using any oil... Actually, your level is only constant because your oil is being diluted.

I'm surprised they even gave the car a dipstick if thats the case...



Let us know if us Euro owners can help you out here Scott.

[pippyrips]

So who is going to take one for the team and contact Audi UK on this matter?

[RI_RS4]

RI_RS4 - dobyou have a view on the performance of Fuchs Titan GT1 oil?

I've only seen one oil sample of Fuchs Titan GT1 5W30 from an owner in Greece who was having issues with his engine at 13000 miles. It was unremarkable, and similar to most other factory approved oils. Flashpoint had dropped to 295F with 1.5% fuel dilution in 5000 miles, which says it did not do a good job of sealing the rings well.

Flashpoint is the point at which volatile components of the oil begin to vaporize off. Given that the average oil temperature in an RS4 run hard is 250F - 270F, and localized temperatures within the engine are even higher, I suspect that those of you using Fuchs see quite a bit of oil consumption, and that the rate accelerates as you accumulate mileage on the oil.

What happens is the the oil does not seal the cylinders well when subjected to a continuous blast of solvent (fuel), but at first the only consumption is the oil that is burnt in the combustion chamber, so the rate of loss is low after an oil change. But, with time, fuel that blows and drips down through the rings loads the oil with fuel, increasing the fuel dilution level. As the fuel dilution level increase, the flashpoint of the oil decreases, and the aromatics in the oil, which are highly active, attack the oil, further breaking it down.

At a certain point, around an average of 1 - 1.5% fuel dilution, all hell breaks loose. The flashpoint drops near 300F and a significant amount of oil starts volatizing and being recycled through the intake manifold. Once this happens, then the valves start loading up. But how fast they load up is dependent upon whether the oil will burn off cleanly during the internal EGR sequence, or whether it leaves deposits behind.

Whatever oil you are using, monitor the oil level carefully, in exactly the same way every time. (After full temperature operation and an appropriate drain down time after stopping.) Keep track of how much oil is lost, and when the consumption seems to accelerate, this is the time to change the oil out. After that point, deposits will form rapidly.

Another thing you can do is to smell the dipstick after full temperature operation. If you start to smell too much fuel, then it's time to change the oil.

[RI_RS4]

This is getting interesting.

In the meantime 5K miles is the absolute maximum my Titan Fuchs is going to see in my car.

It is yet another reason why cars might not be producing 414bhp - because they're only flowing 90% of the air they should.

- Permanent short distance driving, frequent cold starts, overrunned OCI´s or problems
in the fuel injection system can cause oil dilution which is significantly higher than
5%. This can be recognized at the oil dipstick, when oil level stays constant or increases.
This will cause high wear in engine components.

I like that bit most.

All you guys who think your car isn't using any oil... Actually, your level is only constant because your oil is being diluted.

I'm surprised they even gave the car a dipstick if thats the case...



Let us know if us Euro owners can help you out here Scott.

You're correct. I saw that happen with Motul 8000 E-tech 0W40 in my engine. I never had an oil loss, but my fuel dilution level went up. I even documented it in a test I performed, where I took multiple oil samples (4) in one day right after an oil change. The fuel dilution percentage went from:
0.75% - after 143 miles of extremely gentle highway driving
1.10% - after 51 more miles of semi-spirited driving, where I never used more then 3/4 throttle
1.65% - after 50 more miles of spirited driving, where i alternated between WOT and zero throttle.
1.65% - after 40 minutes of idling

During this time, the flashpoint dropped as follows:

365F
345F
280F
280F

As for what you can do. Formally document all of your issues with misfires. Those of you who have had valve problems, document these. Send them all formally to whoever is in charge of Audi UK. They need to see that owners are now aware that these are not isolated problems. Also, ask all your other FSI brethren to do the same. This is not limited to the RS4 engine. Every FSI engine that Audi and VW manufacture have the same issue. Contact the R8 owners. They are beginning to experience the same issues, but they are a very isolated lot, not conversing with the more lowly Audi owners.

[Jezzer]

I have heard people say a large amount of RS4s are smoking and smelling of oil on start up what could be causing this.

[RI_RS4]

I have heard people say a large amount of RS4s are smoking and smelling of oil on start up what could be causing this.

Some of the "smoke" is actually soot. The FSI engine is designed to be extremely rich on startup, and as such creates a lot of soot.

If the "smoke" is blue/gray oil smoke, then it is most likely blow by through the rings, due to fuel dilution. Diluted oil has a lower viscosity. When the engine is cold at startup, the lower viscosity oil does not effectively seal the rings, causing oil to blow by and be burnt. Unfortunately, this is a cumulative process. Such oil consumption causes deposits on the rings. In addition, fuel diluted oil can become quite acidic if the oil is allowed to stay in past it useful life. These acids will micro-etch the rings, also causing blow by. Since the cylinder walls are essentially glass in the RS4 engine, clean rings are absolutely required to create a good seal.

[pippyrips]

I have heard people say a large amount of RS4s are smoking and smelling of oil on start up what could be causing this.

Some of the "smoke" is actually soot. The FSI engine is designed to be extremely rich on startup, and as such creates a lot of soot.

If the "smoke" is blue/gray oil smoke, then it is most likely blow by through the rings, due to fuel dilution. Diluted oil has a lower viscosity. When the engine is cold at startup, the lower viscosity oil does not effectively seal the rings, causing oil to blow by and be burnt. Unfortunately, this is a cumulative process. Such oil consumption causes deposits on the rings. In addition, fuel diluted oil can become quite acidic if the oil is allowed to stay in past it useful life. These acids will micro-etch the rings, also causing blow by. Since the cylinder walls are essentially glass in the RS4 engine, clean rings are absolutely required to create a good seal.

So once 'etched' i guess there is nothing you can do?

Also is it a big problem or does it simply mean you puff out smoke on start-up?

[RI_RS4]

So once 'etched' i guess there is nothing you can do?

Also is it a big problem or does it simply mean you puff out smoke on start-up?

If there is minor chemical etching, that can often be removed by application of a high ester content oil. Fuchs GT1 may be good at that, but I have no experience with it. RLI Biosyn will definitely clean up some of the mess that a previous oil has made. The problem in Europe is that the regulations require the automakers to minimize oil changes, thus pushing change intervals to 10k/15K/20K miles. The longer the oil is in the engine, the higher the acid buildup becomes, and there is eventually a point of no return where it does unrepairable damage to the engine, by causing pitting of rings, cams, bearings ... etc. Best remedy is to change the oil early and often.

As for puff of smoke, it's a symptom of poor ring seal at low temperature and of fuel dilution. If smoke is coming out the tailpipe, then it's a good bet that it's also being deposited on the valves. It's only a matter of time before you start getting misfires and loss of power.

[SR71]

RI_RS4,

I never got round to analysing my oil at the last change but the quote I got from www.oilanalysis.org.uk was £100 (=USD$150 at present exchange rates) for a full analysis including gas chromatography to analyse fuel dilution levels.

Is there a standard template you have been using which details what properties of the oil you are testing for? By all means PM me so that I can make sure I'm testing for the same thing.

That said, maybe it is just cheaper for me to send oil samples to your tribologist? It would also mean we can start adding Euro spec results to your data.

Based on your comments above Titan Fuchs GT1 after 5000 miles is as good as Motul 8000 E-tech 0W40 after ~200 miles if reduction in flashpoint is the consideration which suggests a rather good oil perhaps?

What kind of dilution levels/flashpoints are you seeing with RLI Biosyn after 5000 miles in the car now that you have been using this blend for some time?

Audi say 3% is absolutely normal....

Sounds like BS to me...

[RI_RS4]

SR,

The dilution depends strongly on the climate and how the cars been driven, but generally it's running between .8% to 1.3% dilution. We have a sample with 1% @ 7800 miles, and 1.29% at 9100 miles on the oil, and even a 1% from a guy who put 10K miles on the oil and ran the hell out of it on the track.

By way of disclosure, I no longer have my RS4. I put 40K miles on it and then had to downsize (upsize) to an A6 to save money due to the economy last year. I still love the car and that engine. And, it turns out that the FSI V6 in the A6 has the same issues, and benefits from the same oil and fuel additive solutions. Soon enough I'll be back into another high performance Audi.


I'd suggest that you contact Terry Dyson http://www.dysonanalysis.com/servicelis ... mkits.html and see about having him run your samples and give you his professional interpretation. It's $99 US, but includes his custom interpretation and guidance. Here's a page that gives an example of his analysis and interpretation.

http://www.dysonanalysis.com/samples.html

If you give him permission to share the results with me, I'll include it in our spreadsheet and share the results with you.