jarrison

I bought a CPO 2008 3.6 Q7 Premium with 40K miles a year ago as my first SUV now that I have 3 children and out grew my Volvo. What I didn't expect from the purchase was getting spoiled by the high quality in the Q7. The car literally puts a smile on my face every time I start it. The car was in the dealer yesterday for the first time in a year and now I am frightened that my smile was short lived and I need a little help from the forum to confirm a few things the service tech at the Tysons Corner VA Audi dealer told me.

I had the check engine light illuminate so I brought the car to the dealer who found code PO300,301,302,303,304,305,306 and that TSP 2014753/7 applied to the problem. This is the carbon build-up on the valves issue. A quick google search on that TSP becomes disturbing quickly by identifying no solution to the buildup. The audi tech suggested "Running the Q7 at 4000-5000 RPMs for 5 minutes once a week for the life of the car to burn through the carbon buildup". And that a manual cleaning of the buildup is not covered by the CPO and will cost me about $1,500. He also said that fuel additives won't help because the additives never touch the area of the build up because of the direct injection component of the engine.

Can that be right? Is anyone else on the forum trying to burn off their carbon build up? Does anyone else find it odd that what appears to be an issue with the FSI engine is not covered by the CPO warrantee?

jarrison

Got this answer back from the dealer today. Reminds me of cleaning out the carborator of my 1970 Nova, just rev it hard.

---------------------------------

From: Nathan [mailto:@penskeautomotive.com]
Sent: Thursday, July 12, 2012 2:49 PM
To: Arrison, James M
Subject: RE: Burning Carbon Off My Valves

The 4k-5k rpm may be a little high. Use premium fuel with 93 or higher octane. Run engine from 3k-4k rpm’s for a few minutes weekly. Thank you.

Nathan
703-XXX-XXXX

From: Arrison, James M
Sent: Thursday, July 12, 2012 2:10 PM
To: Nathan
Subject: Burning Carbon Off My Valves

Nathan,

Thanks for your service on Tuesday 7/10/12 for my 2008 Q7. Please confirm 2 items from our discussion:

1. The removal of the carbon buildup from my valves is not covered by my CPO warrantee
2. The only way to prevent future carbon buildup is to run the engine between 4,000-5,000 RPM for 5 minutes once a week

The above two items seem hard to believe so please confirm I heard you correctly.

Thanks,
Jamie

arkbbq

I bought my '07 Q7 4.2 new in the summer of '06, and the carbonization problem surfaced in 2010. The new car warranty paid for the cleaning, and the advisor showed me the warranty charge for the treatment was $795. So the $1500 seems high.

-ark

Jusforfun

Suggest your dealer gets a Terraclean system.

I first saw it on Wheeler Dealers.

At least google it and form your own opinion.

We need something of this nature but I was not too happy to read on another forum that they disconnect the battery as part of the job. Dont know if its true but thats not a good idea on a Q7 unless you have a VCDS handy and note the battery code first.

jarrison

Thanks for the Terraclean tip!! With so many Audi dealerships around the DC area I'll call ahead and go to the one that has it.

Any opinion on whether the high RPM recomendation is a valid prevention method?

Jusforfun

Yes it helps but its not a realistic, complete or permanent solution. It is the combination of the fuel we burn and the engine technology that is leading to carbon build up under normal running conditions.
All engines like to be driven hard now and again but you shouldn't have leave burnout streaks 'joke' around town because your mechanic said so!
Terraclean would seem to be an ideal way to service this issue but it is very new to the market. I expect we will see this or a similar tech being introduced as part of fixed service soon enough.
Well, until Audi introduce a solution into the combustion cycle to deal with it at source.

jarrison

The CEL came on again and the 50K mile service was due at the time so back to the dealer. After a full week at the dealership my '08 Q7 has the chronic carbon buildup problem where the scrape is the only solution. I was quoted 8hrs of labor and $200 for parts for a grand total of $1231.27. Audi is classifying the known carbon buildup issue as "environmental" and won't cover it with my CPO warranty or my purchased service package. Also they found my front brakes and rotors need replacing for $1197.00. Driving the Audi is getting a whole lot less fun for that price.

Any advice? Are others on the forum paying prices like this and just not complaining? The RS4 guys are all up in arms but the Q7 guys are quiet. Maybe $950 for the service package, $1197 for brakes and $1231 for the carbon scrape off for a total of $3,378 is the cost of admission to drive a car for one year since I bought it from the Audi dealer CPO.

Any advice?

chickdr

The brakes can be done for a lot less if you buy the parts on EBay and have them installed at an indie shop. I bought front and rear pads/sensors for a little over $100 and spent $200 on installation vs the $800 quote I got for the same thing at my dealer. I would ask the indie for a quote on the carbon buildup treatment. Check this example for front rotors/pads/sensors($235 shipped...):

http://www.ebay.com/itm/FRONT-KIT-Pr...fd9a17&vxp=mtr

DUTCH VanAtlanta

I have heard very good things about BG 44K for carbon buildup removal and prevention; although I've never had to need to use it. It is apparently used regularly by high end German dealer service departments; and is supposed to be the one product that is not "snake oil".

I don't know if it will solve the problem in Audi engines, but it would be a relatively inexpensive first step to try.

J. Patterson

The carbon build up in the intake and on the intake valves is a result of their being no fuel vapor in the intake to clean away the oil blow by created by the positive crankcase ventilation system. All of the direct injection engines have the potential to develop the problem but all of them do not exhibit it. A properly functioning PCV system is important to reduce the amount of oil blow by to the intake. Some engines simply have more blow by and consume a bit more oil than others due to production and wear variation. More blow by will introduce more oil to the intake and with no fuel vapor there to constantly clean it, carbon will accumulate. BG44 might help to prevent the problem but it will have to be sucked into the intake via a vacuum port. Putting it in the fuel will do nothing as it will never contact the area with the carbon. Only manual cleaning is going to correct that. I would shop a bit for pricing. It is not a quick job however as the intake must be opened and each valve polished. The one thing to remember as you pay the bill is the increased fuel mileage of the Direct injection engine has likely saved enough fuel to outweigh the cost of the cleaning. There is hope for the future as manufacturers are now starting to add another fuel injector in the intake before the valves in addition to the direct injection in the cylinders. This will add some cleaning vapor where it is needed. Newer designs also have better oil vapor trapping in the pcv systems to return the oil to the crankcase rather than sending it to the intake to be burned. Race cars use a catch can. Diesels don't seem to develop the problem though they have been direct injected for decades.
Good luck. As to your brakes. They are easy to do. Shop for an independent mechanic. There are many sources for rotors that are of good quality and far less expensive than dealer pricing.