S5 FSI engines doomed due to intake manifold carbon build-up ?

[Elberoth]

I thought it may be an interesting (if horryfing !) read for many S5 owners.

In short, with direct injection, fuel is sprayed directly into the combustion chamber. Nothing is truly cleaning the intake valves from PCV gunk & blowby.

After just a few thousands of miles, your engine starts to look like this, impeding performance by as much as 40hp :wall::

(pictured RS4 engine with just 40.000 miles)



and here how it should look line (with all the gunk removed):



Seems that all FSI engines have this problem S5 4.2FSI, RS4/R8 4.2FSI, 2.0FSI etc.

You don't really see this issue as much with older port injection engines (non FSI engines) because fuel is cleaning the valve & surrounding area.

More on this topic (RS4 forum):

http://www.audizine.com/forum/showthread.php?t=334489
http://www.audizine.com/forum/showthread.php?t=322587

[08lichmanj]

woah i have a 2.0 and this is shitty

[Elberoth]

Unfortunately, same shit with 2.0FSI :-(

[AFizzle87]

thats why i got a catch can!!!!! also meth helps

[rs4-380]

Although this really isn't new news, they (audi, other manufacturers, etc) haven't really come up with any way to combat it. There also doesn't seem to be a consensus on how to prevent it at this time.

Engines that are driven "leisurely" will surely be more susceptible.

[Ynnekdude]

Seems as if a catch-can may be needed... I'm looking into the costs at the moment and planning on discussing it with the dealer. It's a shame such great technology has such a grim eventual downfall. The cleanup for the RS4 owner was very expensive, and had to be done by a private shop. The dealer's "cleanup" was rather pathetic IMO. I don't want to have to deal with that headache.

[SixthGear]

Seems as if a catch-can may be needed... I'm looking into the costs at the moment and planning on discussing it with the dealer. It's a shame such great technology has such a grim eventual downfall. The cleanup for the RS4 owner was very expensive, and had to be done by a private shop. The dealer's "cleanup" was rather pathetic IMO. I don't want to have to deal with that headache.

Can you let me know the results of your conversation? I'd very much like to know.

Will a catch-can void the warranty? Will it even help?

My car arrives in 2 months and I'd like to do whatever I can from the get-go. What I've seen on the forums hasn't been encouraging and it's just degenerating into bickering over technical details.

I think the whole thing sucks.

[Akatsuki...]

best way is to find where the pcv reroutes and hook up a catch can there. there isn't as much demand for the larger DI engines as there isn't a demand yet.
bsh has catch cans for FSI and TSI 2.0T engines, so those 2.0T a5 owners are able to get one.

[FarmerBob]

http://www.audizine.com/forum/showthread.php?t=336570

Cross post from the "part 2" thread. Straight from the horses mouth for all the non-believers out there.

Quote:
Originally Posted by RS4POWER View Post
Here is a good read for everyone thinking that this is not a problem/issue.
They seem to know about it all too well, they just haven't had the necessary pressure to force them to do something. For those that are serious about getting a database together and taking serious action against audi there is somebody that has been documenting all the incidents and has all he needs to pursue.
We would need good representation so if anyone has legal background and would like to step up, please post here or PM me.

I have a lot more info like this for those interested.

Start with this even though I believe this has been circulated before on either AW/QW RS4 section...

VW patent acknowledging the intake valve deposit issue

Directly from the technical staff of VAG is complete acknowledgment of the FSI intake valve deposit issue, and it's impacts, including: decreased performance, misfires, catalytic converter damage ... etc.


"Gasoline engines with direct injection of the fuel into the combustion chamber, i.e., not into the intake port, suffer especially from the problem of the formation of carbon deposits on components. Carbon deposits form especially in the neck region of intake valves. A more exact analysis of how these carbon deposits form leads to the following result: Oil and fuel constituents first form a sticky coating on the components. These constituents are chiefly long-chain and branched-chain hydrocarbons, i.e., the low-volatility components of oil and fuel. Aromatic compounds adhere especially well. This sticky base coating serves as a base for the deposition of soot particles. This results in a porous surface, in which oil and fuel particles in turn become embedded. This process is a circular process, by which the coating thickness of the carbon deposits continuously increases. Especially in the area of the intake valves, the deposits originate from blowby gases and from internal and external exhaust gas recirculation, and in this process, the blowby gasses and the recirculated exhaust gas come into direct contact with the intake valve."

"Especially in the area of the neck of the intake valves, excessive carbon deposits have extremely negative effects for the following reasons: In the case of Otto direct injectors, the successful ignition of the stratified charge depends to a great extent on the correct development of the internal cylinder flow, which ensures reliable transport of the injected fuel to the spark plug to guarantee reliable ignition at the spark plug. However, a coating of carbon deposits in the neck region of the intake valve may interfere so strongly with the tumble flow that ignition failures may occur there as a result. Under certain circumstances, however, ignition failures can lead to irreversible damage of a catalytic converter installed in the exhaust gas tract for purifying the exhaust gas. Furthermore, the coating of carbon deposits in the neck region of the intake valve causes flow resistance, which can lead to significant performance losses due to insufficient cylinder filling, especially in the upper load and speed range of the internal combustion engine. In addition, the carbon deposits in the neck region of the intake valve may prevent correct valve closing, which leads to compression losses and thus sporadic ignition failures. This in turn could irreversibly damage the catalytic converter. There is the potential for small particles to break away from the coating of carbon deposits in the neck region of the intake valve and get into the catalytic converter. These hot particles may then cause secondary reaction and corresponding local damage of the catalytic converter. For example, a hole may be burned in the structure of the catalytic converter."

"Globular deposits are found especially on the valve stem downstream from a partition plate in the intake port. Due to the dripping of high-boiling hydrocarbons from the partition plate towards the valve neck or valve stem, globular carbon deposits eventually form there by the sequence of events explained above. These deposits on the valve stem can result in flow deficits due to undesired swirling and turbulent flow around the globular carbon deposits. This may persistently interfere with the formation of stable tumble flow from cycle to cycle."

"A possible solution would be to keep these sources of deposits away, for example, from the intake valve, by completely eliminating exhaust gas recirculation and the introduction of blowby gases into the intake port. However with the combustion behavior of modern reciprocating internal combustion engines, at least external exhaust gas recirculation and the introduction of blowby gases into the intake port are absolutely necessary for reasons of emission control and fuel consumption, so that this approach is not possible. "
Direct Injection Internal Combustion Engine

[boomer]

I had begun to notice S5(09) with 27k miles was beginning to start roughly and just not "feeling right". Occasionally took 2 or 3 attempts to start and seemed a little sluggish. Took to dealer for door sensor issue and began to talk to long time Audi technician who acknowledged seeing more problems with the FSI carbon buildup in most models. Had him remove intake assemby and clean all valves(8hrs of labor) and "found the valves to be very dirty and gummed up. Also found the intake to be very dirty and gummed up." Quote taken from work sheet. Pictures on cell phone just plain nasty looking. 90% of my miles are freeway at 75-90mph. Use only Amoco Ultimate and add prestone octane booster/cleaner on occasion and still this!! Billed me $500 but I am certainly going to suggest that I was having a problem with performance and this should be covered--we will see. Tech is checking with Audi about preventive measures. I will let you know. Oh, by the way car starts like new and runs beautifully again but damn I don't want to spend $500 every 20k or so!!!

[twhelans]

Try Sunoco, Mobile or Shell. Better gas with detergent. Amoco ain't Amoco anymore, its BP. Octane boost isn't what you need, you need something like Techron fuel additive or Sea Foam.

[Akatsuki...]

Try Sunoco, Mobile or Shell. Better gas with detergent. Amoco ain't Amoco anymore, its BP. Octane boost isn't what you need, you need something like Techron fuel additive or Sea Foam.

The nitrogren gas wont help FSI.. its directly injected in the chamber, no gas even hits the intake manifold..

[MDS5]

I just had my intake manifold looked at by a reputable shop in my area and it was clean. I have 35,000 miles. I guess it doesn't happen to all engines?

[twhelans]

The nitrogren gas wont help FSI.. its directly injected in the chamber, no gas even hits the intake manifold..

My bad.. I thought the carbon mess came from as a result of the combustion and it was worse based on the amount of crap in the gas.. I guess my using good gas and a regular cleaner is a waste. Must be another reason that my engine with 23K on it is clean as new.

[cleanS5]

Could one's driving style contribute to the problem?

[rs4-380]

this peaked my interest, so I looked at the PCV system today. It is very similar to the RS4 system in that it utilizes a triple vortex oil separator (I do not know if it is the exact same unit). Unlike the RS4, which has hoses and vents going to both valve covers, the S5 only has a hose going to the driver side valve cover. The provision is there for one on the passenger side, but it is plugged. I would have to imagine that this alone would lead to less overall oil vapor entering the system.

The separator bolts directly to the elbow between the throttle body and manifold. My inclination would be to put a catch can AFTER the factory separator. As the separator has a built in oil drain/return it would mean you would be losing less oil (drained from the catch can) and also mean that the catch can would fill less often as the separator would (theoretically) be taking care of the majority of the nasty stuff. That being said, because it bolts directly to the elbow, there is no easy way to add a catch can in this position. you could theoretically do it but it would require relocating the separator and having some custom fittings/adapters made up. That leaves putting the catch can BEFORE the separator, which from an install standpoint should not be a problem as a hose can be run in place of the stock hose (from the VC to the separator) going from the VC to the catch can inlet, and from the catch can outlet to the separator. I do not see any technical reason this would be an issue, but I do not know the intricacies of the factory separator (it relies alot on vacuum/pressure differentials).

I think this may be a damned if you do damned if you don't thing. It the buildup does turn out to be a widespread issue (on S5's) adding a catch can MAY prevent it (or slow it) but it also may give the dealer a reason to turn their head if it does get bad. I don't want to argue about the difference between what what dealers can legally do with warranties and what actually happens, but given other's experiences, it is something to be aware of. Of course doing nothing and crossing your fingers (and going to the dealer if there are issues) could end up badly as well and even then, once out of warranty who wants to pull the manifold and abrade the valves ever 20k miles?

It's a tough situation, not sure where I stand yet. The above post about it happening on an S5 does not make me feel good however...

[rs4-380]

I just had my intake manifold looked at by a reputable shop in my area and it was clean. I have 35,000 miles. I guess it doesn't happen to all engines?

the actual issue is more with buildup on the valves. Looking in the manifold won't show much in this regard, the manifold has to be pulled (or a videoscope used)

[boomer]

update on my S5 and $500/8hr valve cleaning expense. Looks like I got my dealer's attention. Great dealership and Audi specialist who I have worked with over 22 years purchasing somewhere in the neighberhood of 20 or more Audis. She tells me we will get this covered but because I brought it in for another problem and didn't really complain formally about rough start and sluggishness that the job got listed as "client requests valve cleaning". Well in retrospect we all agree that my diagnosis was correct and this IS an Audi problem and that they should cover it. We will see and I do have the personal email address of the head of Audi North America and will use it if necessary. Bigger concern is how to prevent it again. If no answers every 20k I will complain of rough start and sluggishness and see what happens. However, generally I trade pretty frequently obviously. I certainly would have an "understanding" before my next car ??RS5 or whatever. Night and day difference in start and acceleration smoothness which although subjective is pretty obvious to me having driven many different Audi models including 08 S5 and 09 S5

[elf_cruiser]

Has anyone thought about or tried using a foam filter insert into the PCV hose? I've done this before on my rockcrawler to prevent oil coming out of the valve cover and into the intake during a rollover. Is it 1/2,5/8,3/4 rubber hose? If so - should be easy to cut the hose, and insert a plastic coupler with a foam filter inside. Just change the filter every XXXX miles.... It would still allow the top end to breath, but would block oil from coming into the intake. Is there a PCV outlet in the bottom end, or just the valve cover?

Or hey, even better - put one of these inline - http://www.summitracing.com/parts/AEI-12301/
a 10 micron filter should block alot of oil. Easy and cheap to change the paper element every so often... I'm assuming that the PCV system on this car is similar to every other car I've worked on... Please let me know if I'm missing something...

[Alkivar]

Has anyone thought about or tried using a foam filter insert into the PCV hose? I've done this before on my rockcrawler to prevent oil coming out of the valve cover and into the intake during a rollover. Is it 1/2,5/8,3/4 rubber hose? If so - should be easy to cut the hose, and insert a plastic coupler with a foam filter inside. Just change the filter every XXXX miles.... It would still allow the top end to breath, but would block oil from coming into the intake. Is there a PCV outlet in the bottom end, or just the valve cover?

Or hey, even better - put one of these inline - http://www.summitracing.com/parts/AEI-12301/
a 10 micron filter should block alot of oil. Easy and cheap to change the paper element every so often... I'm assuming that the PCV system on this car is similar to every other car I've worked on... Please let me know if I'm missing something...

thats basically what a catch can is... only with a much larger retention volume... a small filter like your suggesting would get plugged up and ruined way too quick to be of any use.

[elf_cruiser]

So what problems are caused if the filter became clogged and the intake was unable to suck quite as much air from the crankcase? Are there sensors monitoring crankcase vacuum?

[Tifosi]

New infomation on this topic: http://www.rs6.com/showthread.php/20...l=1#post185517

[switchface]

update on my S5 and $500/8hr valve cleaning expense. Looks like I got my dealer's attention. Great dealership and Audi specialist who I have worked with over 22 years purchasing somewhere in the neighberhood of 20 or more Audis. She tells me we will get this covered but because I brought it in for another problem and didn't really complain formally about rough start and sluggishness that the job got listed as "client requests valve cleaning". Well in retrospect we all agree that my diagnosis was correct and this IS an Audi problem and that they should cover it. We will see and I do have the personal email address of the head of Audi North America and will use it if necessary. Bigger concern is how to prevent it again. If no answers every 20k I will complain of rough start and sluggishness and see what happens. However, generally I trade pretty frequently obviously. I certainly would have an "understanding" before my next car ??RS5 or whatever. Night and day difference in start and acceleration smoothness which although subjective is pretty obvious to me having driven many different Audi models including 08 S5 and 09 S5

That's great that they took care of that for you...I'd think after buying 20+ cars from them that they'd do backflips when you walked in. :D

If you have the head of Audi NA's ear, let him know what his enthusiasts are encountering so they can fix it.

[elf_cruiser]

"A possible solution would be to keep these sources of deposits away, for example, from the intake valve, by completely eliminating exhaust gas recirculation and the introduction of blowby gases into the intake port. However with the combustion behavior of modern reciprocating internal combustion engines, at least external exhaust gas recirculation and the introduction of blowby gases into the intake port are absolutely necessary for reasons of emission control and fuel consumption, so that this approach is not possible. "
Direct Injection Internal Combustion Engine

I'm going to attempt to find out what is and is not "possible" with regards to this quote...

[Tanner]

Well that is possible, venting it into the atmosphere but it would be a no-no obviously from an emissions point of view.

Note that this isn't just an Audi issue, it's an issue for all direct injection engines. Toyota at least has recognized the problem and has a port-injector that is used from time to time to splash a bit of fuel on the intake valve to help keep it clean. I'd suspect that the issue will crop up on these engines but at a much higher mileage.

I was looking into the Mini Coopers and since BMW moved over to a direct injection turbocharged engine starting with the 2007 model, they too are seeing issues with cold start issues and misfires which seems to be caused by buildup on the intake valve, but more so on the fourth cylinder due to how the blowby gases are introduced back into the intake, seems like what the S5 is doing.

At the end of the day, I know for the 2.0T, even if you use a catch can or some trick filter like the ProVent oil separator, build up on the intake valves will still occur due to the overlap in the valve timing which I wasn't aware of previously. Overlap is there to help increase low-end torque while improving fuel efficiency and it's probably present in every Audi FSI engine. Well until the intake valve is covered in gunk along with the intake manifold flaps.

[boomer]

That's great that they took care of that for you...I'd think after buying 20+ cars from them that they'd do backflips when you walked in. :D

If you have the head of Audi NA's ear, let him know what his enthusiasts are encountering so they can fix it.

Audi NA did cover the expense and according to the head technician who just returned from a national meeting they are aware of the problem and are working on a fix. He said he would get back with me w/in a few weeks when he hears more and I will update.

[bryzf1]

Audi NA did cover the expense and according to the head technician who just returned from a national meeting they are aware of the problem and are working on a fix. He said he would get back with me w/in a few weeks when he hears more and I will update.

I look forward to hearing what "fix" they come up with

[flyfishing]

edmunds long term test car is s5. we should all email thema about this problem and maybe they will look into it and make it a bigger issue!

[GordonC]

New info? I read as much as I could about the carbon buildup on FSI engines before buying my S5 in June. I just came across a post yesterday on www.a5oc.com that contained information that I had never read before - the post by Tony - PES was discussing production delays because of a redesign of their supercharger kit for the S5 4.2 V8, and said

In mid 2009 Audi totally changed the inlet manifold, fuel rails, flaps, as well as the hole configuration into the head. Why? Your guess is as good as mine as the car makes the same stock HP as 2008. We had to make changes for the 2009 and redesign the fuel rails as well as a few other parts.

My guess might be that Audi were aware of the carbon buildup problems showing up on the first couple of years of production of the FSI engines, and changed the heads and intake components to try to reduce buildup?

Is there any cross-reference of people who've had excessive carbon buildup in an S5 FSI V8 vs. model year? Are the post mid-09 cars suffering less from this issue?

[switchface]

Not sure this applies 100% to this situation, but thought I'd pass it along. Perhaps a step in the right direction?

http://www.autoweek.com/article/2010...NEWS/100929873


Volkswagen AG has agreed to pay maintenance costs under a proposed settlement in a class-action lawsuit over sludge-damaged engines in 479,768 VW and Audi models.

Judge Joseph Tauro of the U.S. District Court in Boston gave conditional approval of the settlement last week. A hearing to approve the final settlement is scheduled for March 11, 2011.

According to court documents, the settlement affects 1997-2004 Audi A4 models and 1998-2004 VW Passat models with 1.8-liter turbocharged engines.

The engines were prone to oil sludge from coking deposits even when maintained according to the automaker's recommended maintenance intervals and oil-quality specifications, court documents show.

“Each plaintiff claims that his or her vehicle was damaged or will suffer future damages as a result of the alleged sludge and coking problems,” court records show.

The multi-state suit was consolidated in Massachusetts in 2006 according to lawyers representing car owners. The suit also claims VW and Audi failed to honor an 8-year unlimited warranty extension issued in 2004 by denying claims brought by vehicle owners with sludge-related engine failures.

VW and Audi have agreed to “cover 100 percent of the maintenance costs for owners/lessees with proper documentation of required oil changes, and 50 percent for those without proper documentation,” plaintiff lawyers said in a statement today.

The settlement also provides owners and lessees eligibility for a 10-year/120,000-mile enhanced oil sludge warranty, according to a statement issued from lawyers Peter McNulty, Kirk Tresemer, and Russell Henkin, who represent the vehicle owners.

All class members who currently own or lease the covered vehicles will also receive revised oil-maintenance recommendations.

A Volkswagen AG spokeswoman said the two sides are still finalizing the settlement.

“The terms haven't been worked out--the exact compensation or remediation is not yet finalized,” the spokeswoman said.

VW said letters will be sent out to owners around Dec. 20, and the final amount of the settlement will be determined by the number and size of claims paid.

VW began notifying owners of the problem in August 2004 after receiving consumer complaints. The automaker's remedies ranged from extending warranties to covering repair costs, including complete engine replacement.

Sludge buildup can cause engine performance to deteriorate, and in extreme cases, engines to lock up.

For more Car news - Automotive Headlines, click here.

Read more: http://www.autoweek.com/article/2010...#ixzz10wP9uxLV

[Nebone]

The above is a completely separate issue. All these award winning motors and they still have issues that most regular motors do not.

[Tanner]

Related to the use of non-synthetic motor oil was it not?

[Scotty@Advanced]

Related to the use of non-synthetic motor oil was it not?

The 1.8t sludging was caused by the extended oil change interval (10,000 miles) and the use of non synthetic oil, small oil capacity, and higher heat generated by the turbocharger.

[JimmyBones]

Until the first reported case of carbon build up shows up I would not worry about it. I have pulled the intake manifold to replace the injectors on a few 2009 S5s and none of them had anything close to the nasty RS4s pictures that you can find.

The 1.8t sludging was caused by the extended oil change interval (10,000 miles) and the use of non synthetic oil, small oil capacity, and higher heat generated by the turbocharger.

What this guy said. I have had three cars that have had this issue with and none of them needed an engine luckily for both the client and me. Audi was covering these repairs for up to eight years/unlimited miles from the production date and one of the three cars that I had to deal with was out of that range by three months so he had to pay for the engine oil flush and other repairs.

[cleanS5]

Part of the solution will be not to baby your car too much. Keep driving it, do the normal oil change interval (not every 10k miles).

[chrissurfr]

I bought my car with 11k miles on it and have been driving the shit out of it.....it def feels faster than when I bought it.....I have had several long distance high speed runs and I feel like some carbon deposits got burned out. Maybe I'm dreaming?!

[elf_cruiser]

I'm going to attempt to find out what is and is not "possible" with regards to this quote...

Just FYI - since this thread popped up again. I've been running the PCV into the atmosphere for many months now with no issues, no power loss, etc... About 11k miles on the car now. I did run some seafoam through the engine back over the summer and it cleaned out a BUNCH of crap - probably due to the first 5k miles with the breather line attached...

Just an update in case anyone was interested...

[GSS5]

I bought my car with 11k miles on it and have been driving the shit out of it.....it def feels faster than when I bought it.....I have had several long distance high speed runs and I feel like some carbon deposits got burned out. Maybe I'm dreaming?!

I think that is possible. I have definitely heard that pushing the car to high revs will clean out the deposits. Horrible on gas especially with the V8, so it's tough to find a balance somewhere in between.

[S5noob]

So do you run with the PCV to the atmosphere (crankcase side), and the other end plugged up (intake side)? Or..? Share your setup please :)

Just FYI - since this thread popped up again. I've been running the PCV into the atmosphere for many months now with no issues, no power loss, etc... About 11k miles on the car now. I did run some seafoam through the engine back over the summer and it cleaned out a BUNCH of crap - probably due to the first 5k miles with the breather line attached...

Just an update in case anyone was interested...

[BayrischerS4]

Had my 2009 S5 in 6weeks ago due to rough starting idle and they replaced all the fule injectors and both high pressure pumps three times only to come up with that there is a large amount of carbon build up on the intake valves, mind you my car only 12,000 miles on it and I drive the car like a bat out of hell 90% of the time with close to redline revs and still build up occured. I too am frustrated that I don't think pulling my cylinder heads off every 12,000 miles and getting the valves cleaned should be counted as part of my routine maintenance.

I love the car but not the engine if it keeps having this problem. It is funny due to the high tech design that my 1970 Camaro is better at cleaning it's valve than my S5. Have to love fuel over the valves for cleaning.