Audi FSI Engine Carbon Build-up Megathread

[frankyd021]

I have a 2007 A4 3.2 Quattro with serious carbon build up issues. The motor has been replaced at around 48k miles under warranty. Audi has given me an additional 12k extension for the motor. I still have constant CEL issues even with the new motor.

[rriter&d]

Questions for you....
how many miles on the car now ? intervals between oil changes ? what brand and octane of fuel do you use ? what kind of driving shorts trips or mostly hiway ? Leadfoot driver or lite footed ? Does it run poorly or hard started when cold in the am ?

[fasttoys]

I use RXP additive once per month or once a Q depending on the car this stuff it eats up carbon. I never had an issue in any of my 6 cars.

Audi S4 11
Porsche 911 S 05
VW 2.0L T GLI 07
BMW M5 V10 06
BMW 328 09
BMW Z4 M coupe 07

[iconoclast]

which cars? only the 328, 2.0 and the s4 are direct injection and the s4 is too new to tell.

[ASU S4]

burrito

[iconoclast]

^excellent contribution.

[NWS4Guy]

The B8 S4 has a thermostat recall under way for MY 2010 and some MY2011 cars. Doing this requires the Supercharger to be pulled. Our Supercharger sits on top of the intake runners, where you can actuate the air flaps and see directly down to the intake valves. CB appears to have been sucessfully defeated for the B8 S4 from this picture a friend with 30,000 miles on his B8 S4 was able to get when they took his Supercharger off:

I must say these look gorgeous for 30K miles!

[Phknlwyr]

2007 Audi S6
Rockville, Maryland
51k as of May 2011
Mobile One 0W 40
Every 5k miles
Always 93 Octane Exxon or Shell
20 miles to and from court most days


I am the second owner, having acquired the car in February 2009 with 14k on the clock. No mods to the car...yet. It's my daily driver. The car started throwing CEL codes in the Fall 2010 when I made a very hard acceleration. The light would flash repeatedly and then stay solid. The first time this happened in November 2010, Audi replaced my coilpacks and air intake flap motor under warranty and the applicable TSB. That cured the CEL for about a week. Another hard acceleration and the CEL was back on. I then noticed that the car bogged down very noticably at 4,000 rpm. It would struggle to accelerate and hard a hard time increasing rpm's. Again, the CEL would flash. I went to the delear in April and they reset the CEL and updated certain software (I do not have the exact software since they still have my car and do not have final paperwork). I was told by the head mechanic there that my car was misfiring very badly on cold starts. The software update seemed to cure the misfires on cold start...for about three days. After the software update, I drove the car three days later and threw an engine code. Back to the dealer with VAG-COM report in hand showing misfires in cylinders 5, 6, & 10. They suggested the 55k service. I suggested that they contact AoA about carbon issues. They got the 55k service from me and I got a full carbon cleaning from them. Picking up the car in 30 minutes. Should be interesting with new plugs, new oil, new filters, and no carbon deposits.

[BEM3]

Update: Due to my continued dissatisfaction with the engine replacement, carbon build-up and cylinder wall wear on my 2008 A4 3.2l Quattro Sedan, Barrier Audi and Audi of America offered their Trade Assist Program where they purchased my A4 back at an agreed to price and sold me a new 2011 S4 Sedan at a discounted price. I ordered the S4 back in late February and it arrived last Friday. The S4 is an absolutely amazing car. I have to give kudos to Barrier Audi for their help, especially since I purchased the A4 new from another dealer, and thank Audi of America for stepping up and making things right.

[cleaver]

Update: Due to my continued dissatisfaction with the engine replacement, carbon build-up and cylinder wall wear on my 2008 A4 3.2l Quattro Sedan, Barrier Audi and Audi of America offered their Trade Assist Program where they purchased my A4 back at an agreed to price and sold me a new 2011 S4 Sedan at a discounted price. I ordered the S4 back in late February and it arrived last Friday. The S4 is an absolutely amazing car. I have to give kudos to Barrier Audi for their help, especially since I purchased the A4 new from another dealer, and thank Audi of America for stepping up and making things right.

Well good for you BEM3; I hope you'll be happy. I'm at about 7k on my new 3.2 short block and 6k on a new passenger-side head; so far, so good. I'm off factory warranty now and on 12/12 "good will" extended warranty at University. I only hope things continue to be OK, as I really want a wagon and Audi only offers FSI 2.0T wagons now in the A4.

[AudiDr1]

We see carbon related issues on a daily basis now, some drivers have tried all kinds of additives to help but nothing seem to work but manual cleaning.
we been using 10w-60 on a few FSI engine for a while now with very positive results, lower oil consumption by a lot and so far hardly any carbon in the intake runners and intake valves.

[iconoclast]

Update: Due to my continued dissatisfaction with the engine replacement, carbon build-up and cylinder wall wear on my 2008 A4 3.2l Quattro Sedan, Barrier Audi and Audi of America offered their Trade Assist Program where they purchased my A4 back at an agreed to price and sold me a new 2011 S4 Sedan at a discounted price. I ordered the S4 back in late February and it arrived last Friday. The S4 is an absolutely amazing car. I have to give kudos to Barrier Audi for their help, especially since I purchased the A4 new from another dealer, and thank Audi of America for stepping up and making things right.

lol, i would do that in hearbeat... makes all the craziness worthwhile.

[routertyty]

Does model year 2011 have this same issue?

[405Z]

You can add me to the list. 2007 RS4, 25K km, oil changes every 6 months at dealer (Castrol) and Shell V Power 91. The car is primarily city driven and sees both granny style driving as well as low gear-high rpm and WOT bursts.

Got the CEL due to multiple misfires when cold. They gave me a couple of bottles of additive and I'm supposed to take the car out for an extended run with it. I'm positive it won't do anything but manual cleaning will not be covered at this point.

[tsmitty]

Great thread. I wonder if Audi's treatment of this issue is improving? Granted, when I think about it, the process I've gone through has been a lengthy one - but my experience has been pretty good in all. My '09 S5 has 27,600 miles on it. Like clockwork, I started experiencing the usual symptoms around 26,000 miles. When my car started misfiring, I took it into the dealership, pretty certain of what the issue was. The additive was the first step. I was surprised that it actually worked pretty well. Then the chronic CELs started. Took it back, they didn't find anything, but provided Audi with a data dump from my car's computer. A month or so later, Audi told the dealer to replace all of my fuel injectors. So they did, and in so doing discovered the usual carbon deposits - which they scrubbed off. This has been done all the while providing me with a 2011 A6 to putter around in. All told, it's pretty hard for me to complain. Still, I don't relish having all this work done when my car goes off warranty in a few years!

[njs509]

i have a 2009 s5 and i just used seafoam to clean it out. i can see i 100% feel a difference. i used to had rough idle when it was cold or sometimes even when it was nice out. i felt a little lag when gunning it .

[Jacon]

i have a 2009 s5 and i just used seafoam to clean it out. i can see i 100% feel a difference. i used to had rough idle when it was cold or sometimes even when it was nice out. i felt a little lag when gunning it .

I was wondering if anyone had tried this. It was an old trick many would use on the old VR6 and 18t motors

[ActivS5]

2008 S5
65k miles
91 Chevron or Shell
Oil changes every 5000-7000 miles
75% highway/25% city

http://www.audizine.com/forum/showth...ng-*Pic-Heavy*

[Midwestuser1]

Does anyone know if the 2010/2011 A6 added a secondary fuel injector to keep the carbon build up off of the vavles?

[drfuelinstein]

All this habub about carbon deposits and the supposed solutions leads me to ask with one of the finest pieces of automotive technology ever developed?

1) What is the scientific causal mechanism for carbon deposits?

2) Is there really a Top Teir Gasoline? Really? what is the difference? Can you prove it?

3) I would ask from all the solution providers from Sea-foam to techron and everything in between..
If you really know the scientific causal mechanism for this phenomena please inform the rest of us?

[Danarone]

Fellow Audi enthusiasts, the carbon buildup problem we face is not solely Audi’s fault. Fighting with Audi will get us nowhere, and may eventually hurt the Audi brand and the resale value of our vehicles.

The lion’s share of guilt lies with government agencies and environmentalists who place an undue burden on auto manufacturers. In the end, it’s the consumer of Direct Injected (DI) engines from BMW, General Motors, Honda, Toyota, Volkswagen and Audi who pay the price in the form of expensive repairs due to carbon buildup.
Why?
Because the EPA and EEA force manufacturers to install antiquated emission control systems on modern engines, even if the system is unnecessary and incompatible. EGR (Exhaust Gas Recirculation) and PCV (Positive Crankcase Ventilation) made sense in 1970 when big displacement carbureted engines pumped raw fuel into the crankcase and exhaust. But DI engines have computer controlled intake systems and highly specialized systems that all but eliminate wasteful byproducts compared to their ancestors. These engines provide a nearly perfect ratio of fuel-to-air and minimal by products from combustion. Yet the EPA and EEA continue to force manufacturers to suffocate and choke these engines with outdated, complicated emission control systems designed for 1970’s dinosaurs. This is what leads to the carbon buildup.

In 1997 The Union of Concerned Scientists compared the emissions of modern cars to pre-control cars. They found 75% less carbon monoxide, 87% less hydrocarbons and 60% less nitrogen oxides. Bear in mind this is a group that would like to severely limit or ban automobile use. Regardless of your politics, you must admit those are some impressive reductions in vehicle emissions. You also must also admit that there is a point of diminishing returns—the point where you are fighting the basic physics of internal combustion to reach an unattainable goal. I believe we have reached that point.

The solution?
I believe we should join forces with enthusiasts from BMW, General Motors, Honda, Toyota and Volkswagen. Together we can encourage the manufacturers to use their lobbying influence and legal prowess to demand change. We seek to scrap the antiquated emission control technologies and develop emission control systems that are optimized for modern engines. The new emission control systems would be offered by manufacturers as a retrofit solution to owners of direct injection engines with carbon buildup. Moving forward, the process of exploring new ways to reduce emissions could produce vehicles that delight drivers and protect the environment in ways yet unimagined.
Are you with me?

Dan

[vandelizer]

I posted this on the pics section, but it looks like here is where most people are posting their car/driving/gas type/oil change stats, which is what this post also has, so I'll re-post it here:


Car: 2006 A4 B7 S-Line Fronttrak (2nd owner)
Mileage: 87,XXX (lots of high way miles)
Gas: 91 oct and 93 oct
Driving styles: Spirited driving, no racing or track days
Extras: Carbonio Cold Air Intake, PCV update, All recalls done, 034 Motorsports turbo intake hose, All maintenance done on time at Certified Audi Service center, Oil changes done every 5,000 miles at Audi
Engine Block all cylinders pic –
Cylinder head 1 w/ burnt valves due to carbon build-up, cylinder 1 PSI = 90, instead of 150 as in the other 3 cylinders

Improper valve seating in Cylinder 1 -

Light shining through valve in cylinder 1 to show improper seating

Faulty valve in cylinder 1 carbon build-up

Faulty valve in cylinder 1 carbon build-up view 2

intake port and valves cyln 1

intake port and valves cyln 2

intake port and valves cyln 3

intake port and valves cyln 4

To make a long and somewhat painful story shorter, here is a bullet list of what happened (with a happy ending):
- Noticed rough idle and running rough in lower gears, at higher RPM not noticeable
- 10-30 miles later check engine light came on
- Stopped by a near by auto zone to have them read the code, cylinder 1 miss fire
- replaced spark plugs, check engine light ~30 miles later
- replaced coil packs, check engine light couple miles later
- took to audi, they said fouled up fuel injector (replaced by extended warranty) didn't fix problem
- Audi asked to tear down engine, 8 hours of labor would be covered by me if the faulty part was NOT covered by extended warranty
- 2 weeks since I took my car in (some delay due to parts not in stock, some delay due to me asking for pictures from dealership, and some delay due to private company inspection authorized by extended warranty company) tech noticed burnt valves in cylinder 1. I asked repeatedly for the service adviser to check for carbon build-up issues during the engine tear down (the reason I requested pictures). I was assured by the service adviser that the carbon build-up was minimal especially for the year and number of miles. I pushed the carbon build-up issue, and asked if that was the cause of the burnt valve, they said they weren't sure. Could be faulty valve lifter, could be the way it was driven (too hard), could be several things. WTH!?
- I spoke with extended warranty company, they said they would send out a private vehicle inspector to determine the cause of the problem. They determined the fault was caused by carbon build-up.
- I was told the extended warranty would not cover the burnt valve, therefore, to fix problem I owed $4,200 to replace cylinder head 1 on engine.
- I flipped
- Calmly spoke with the service adviser and asked to speak with the service manager. Told both, I have had my car serviced here for every single maintenance (except one down at a different Audi dealership), and said so what you're telling me that even though I pay a hefty price to keep my vehicle properly maintained I can expect this type of problem to happen. Also mentioned that if I were to pay for this problem to be fixed I don't want it to happen again soon, for instance, to cylinder 2,3, and/or 4. I asked how would they prevent this from happening again. They said these things happen, but they would speak with Audi Tech (Audi of America) to determine the appropriate action.
-Service Manager ( Thankfully a respectable man who stood behind his work) Robert Fletcher of Audi of Albuquerque, said he worked with Audi Tech and they authorized a 1-time good will 50/50 servicing. Essentially, I would pay half and Audi would pay the other half. Also they removed the labor charge for the engine tear down, oh and Mr. Fletcher assured me they would clean the other cylinders, including intake ports and back of valves. Replaced timing belt as well, since engine was torn down already.
- I was given peace of mind that I would not have to worry about this again, at least not for another 87,XXX miles. All for ~$1,600
- The difference was night and day. I was driving a brand new 2012 A3 TDI for the approx 3 weeks I was waiting to fix my car. Of course I was expecting my 2006 car to run at least a little rougher than the brand new loaner (especially since I have a leaky motor mount which leads to a little more engine feeling in the cabin of the car, but it was not in horrible condition.). I was wrong, my car is purring like a kitten, and it is so smooth! I am so happy with the results. It sounds so good, and the higher RPM pull is a huge difference!! Not sure about the MPG difference yet since its been less than a week, but I'll find out. Hope this info helps someone

[B45H1R]

Had it cleaned 2 weeks ago. Reportedly very difficult to clean. I imagine so for a car with 67K miles on it without a previous clean. Glad to have had it done. I'll be honest, I can't tell much of a difference, but I rarely flog it. When I do, It always pulls hard. Pulled hard before, and pulls hard still.

Just as a note. The plugs were changed, and also had an oil change and some Motul put in. The garage (BARTuning in Houston) didn't take a pic of the oil change, but since they'd done a previous carbon clean on another RS4 with the same oil change, using the same oil, I borrowed the last two pics from that photo stream. Every other pic is 100% my car.

It will be on sale this week.


Before:


















After:

[Midwestuser1]

I copied and pasted this from a MB forum. Does anyone know if this is indeed true?

"Actually VW/Audi/Porsche/Lambo have come up with a fix that will soon be integrated into all their new DI engines.

They simply kept the DI injector inside the cylinder and placed another injector back inside the port where it was originally so the detergent fuels can clean the intake system as you drive. They call it dual injection.... simple right? Yup! But Mercedes didn't care to look around before they jumped into Direct Injection... let's hope that this tech guy is wrong and that MB did address the problem in some way."

[FarmerBob]

If you look at post # 87 above (pic of engine head for B8 S4 after 30,000 miles), doesn't that mean Audi did put in a new injector into the port, so fuel detergents circulate to prevent carbon build up? Isn't this problem solved with a new design to Audi's engines, at least for the B8 S4?

[ronin_z]

Sorry if this is a newb question, but is the build-up still an issue for the 2012 A4's?

[boiseauctioneer]

I noticed the D3 S8 isnt listed. Not as common of an issue?

[xTomKx]

All this time and still no easy fix. Has anybody done a seafoam treatment and pulled the intake off afterwards?

[ewwmatic]

I am a fairly new A4 B7 owner and I am already dealing with the carbon build up issue which seems to be causing random misfires which triggered the CEL. Does anyone have any advice? Should I listen to the dealership or try using Seafoam or BG 44K?

Also, on another note, is it common for dealerships to charge for kits such as a Fuel Injector Puller Tool? Are these tools not reusable? I apologize in advance if any of this has been previously addressed in this thread. Thank you for reading.

[flyfishing]

Boom just had my 09 s5 carbon cleaned under warranty. Tip: tip your adviser every year and always write good reviews. My warranty was about to expire and they said I needed a carbon cleaning.

No idea on gas mileage yet, but it def pulls harder! Tech said my car was caked in carbon. I guess I'll drive it another couple more years and when it's time for next carbon cleaning, just sell or trade it in for another car.

[dhinez]

I'm about to do this in a couple weeks. I'm also going to install the runner flap delete kit at the same time.

[omnupe]

Just had my car "cleaned" for the second time. When I took my car in for a CEL I was told that it would not be covered as my warranty had just expired. Luckily, I told them about the first "cleaning" at another dealership and they did it free of charge. I really love this car, almost have it paid off and would really love to keep it but this is a PITA and I would hate to have to go through this ever 15K miles...

[jaybquick@JHM]

Here is what we found on our latest in house R and D car upon purchase. 2008 S5 V8 6-speed MT with 80k.



This S5 now has a sliding clutch after the cleaning and JHM intake spacer install, so the car woke up a ton.

We do the RS4s regularly and see 10 to 30whp gains depending on mods.

[S5 Jammy]

Just received my Audi letter stating extended warranty for carbon buildup issues. Does anyone know if Audi will check even if no CEL comes on?

[Dad A3]

Well at 85K miles it finally happened. Did the $900 carbon cleaning. Got the car back and 30 miles later I get CEL. Car goes back in the shop tomorrow.

[KARAKAS]

Here is my experience with my S5. I bought the car with 52k miles on it, out of warranty. The original owner had the AudiCare so every maintenance was performed by the dealer so I bought it with no hesitation.

At around 54k, the car had intermittent misfire. I took it to the dealership and below pictures are the intake valves explaining why car was misfiring. Last week, at 66k miles, it also started to misfire, which only after 12k miles. This time I removed the spark plugs at cylinders #5,#6, #7 and #8 (bank 2) and they were covered with heavy carbon build up. Looking through the spark plug hole, top of the piston and all surfaces of the combustion chamber is covered with black nasty carbon. The car is not drivable, it rumbles and dies off due to misfire.

I am very disappointed with this known problem by Audi and wonder if Audi S5/RS4/etc. owners have started to sign some kind of a petition stating that Audi made a car that has a design flaw. If you take your car to the dealer, the valves will be cleaned for $800-$1000. Knowing that the issue will repeat itself every 20-30k miles (I am being optimistic), is this an acceptable resolution? Audi is not fixing the problem, they are only treating the symptom. Reading the comments from every S5 owner here, we all look for a resolution and trying to prevent the carbon build up reoccurance after the first clean up. This should not be our task to resolve the problem, it should have been Audi's if they care about their customers.

I am hoping Audi will do something about these high end performance cars, otherwise they will be losing customers. I have been sharing these pictures everywhere I can to let everyone know about what their RS4, S5, S6, etc can suffer from.

[jayulzvern]

I wonder what gas (octane & brand) everyone is using and if that correlates with some of the symptoms.

KARAKAS
- I agree with you that Audi's solution is insufficient but you have to consider why this is happening. BMW prevents this from happening in their direct injection engines by having a second injector in the intake to spray a solvent(gas) onto the intake runners/valves to help clean them. That's why they have to add other technologies to help improve MPG like their efficient dynamics cars.

Its not a simple problem to deal with in a elegant way. If anyone comes up with a good solution then I am sure AoA would love to hear about it.

[CrazyCal]

Fellow Audi enthusiasts, the carbon buildup problem we face is not solely Audi’s fault. Fighting with Audi will get us nowhere, and may eventually hurt the Audi brand and the resale value of our vehicles.

The lion’s share of guilt lies with government agencies and environmentalists who place an undue burden on auto manufacturers. In the end, it’s the consumer of Direct Injected (DI) engines from BMW, General Motors, Honda, Toyota, Volkswagen and Audi who pay the price in the form of expensive repairs due to carbon buildup.
Why?
Because the EPA and EEA force manufacturers to install antiquated emission control systems on modern engines, even if the system is unnecessary and incompatible. EGR (Exhaust Gas Recirculation) and PCV (Positive Crankcase Ventilation) made sense in 1970 when big displacement carbureted engines pumped raw fuel into the crankcase and exhaust. But DI engines have computer controlled intake systems and highly specialized systems that all but eliminate wasteful byproducts compared to their ancestors. These engines provide a nearly perfect ratio of fuel-to-air and minimal by products from combustion. Yet the EPA and EEA continue to force manufacturers to suffocate and choke these engines with outdated, complicated emission control systems designed for 1970’s dinosaurs. This is what leads to the carbon buildup.

In 1997 The Union of Concerned Scientists compared the emissions of modern cars to pre-control cars. They found 75% less carbon monoxide, 87% less hydrocarbons and 60% less nitrogen oxides. Bear in mind this is a group that would like to severely limit or ban automobile use. Regardless of your politics, you must admit those are some impressive reductions in vehicle emissions. You also must also admit that there is a point of diminishing returns—the point where you are fighting the basic physics of internal combustion to reach an unattainable goal. I believe we have reached that point.

The solution?
I believe we should join forces with enthusiasts from BMW, General Motors, Honda, Toyota and Volkswagen. Together we can encourage the manufacturers to use their lobbying influence and legal prowess to demand change. We seek to scrap the antiquated emission control technologies and develop emission control systems that are optimized for modern engines. The new emission control systems would be offered by manufacturers as a retrofit solution to owners of direct injection engines with carbon buildup. Moving forward, the process of exploring new ways to reduce emissions could produce vehicles that delight drivers and protect the environment in ways yet unimagined.
Are you with me?

Dan

My wife and I were set on purchasing a Q5 3.2L, but discovering this issue has put a screeching halt to any purchase of a vehicle with DI engine. I'm very saddened by this as I love the way the Q5 drives and looks. It would've made a great family vehicle.

I agree with all of the above comments about the antiquated emissions systems. So.... my question is.....

Has anyone tried removing all of the EVAP/EGR/Emissions garbage?
My only experience is with the 1.8T, but I have essentially eliminated all of the emissions junk on my engine. It runs great and I don't ever have to worry about any EGR issues, or SAI issues, etc
My SAI is the only part of all of this that had to be tuned out.

But, by avoiding the recirculation of byproduct, would it help avoid this carbon buildup?

[irulea2]

I'm looking into the carbon cleaning locally in Phoenix and this was advised. Thoughts? How effective is this for the cleaning? My rs4 has 99k on it and the service records do not indicate this was ever done.

They used BG products and their carbon cleaning procedure.

Basically this...

[Audibot]

I'm looking into the carbon cleaning locally in Phoenix and this was advised. Thoughts? How effective is this for the cleaning? My rs4 has 99k on it and the service records do not indicate this was ever done.

They used BG products and their carbon cleaning procedure.

Basically this...

I don't have an RS4 (mine is a B7 A4), but from looking around and talking, plus the experience of getting it done myself, the BG treatment won't perform nearly as good a cleaning as manually scraping or blasting it off. The carbon is really baked on there. BG treatment is a nice after cleaning to rinse away any lingering deposits.

Seriously, get the manual cleaning done at the very least (and maybe add on the BG treatment). The car will seriously wake up (as mine has for me) and you'll be wondering why you didn't do it sooner!