S4 Carbon cleaned

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just getting a idea here, has anyone had the S4 engine carbon cleaned. Is it recommended, did it work, were you happy and price ?
 
Was this not just a V8 issue due to it being NA

Could be wrong though :)
 
I asked my trusted Indy about this about a month ago and he said that it was up to me... He said they were getting one or 2 TFSI (mainly 2.0) engines in each week to get cleaned - the owners were all coming in with check engine lights on.

This is just one mid-sized garage though, not really representative.
 
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It is a direct injection engine so there will be carbon buildup over time.
 
Was there not a posting some time ago, on the SRS website with a copy of the "workshop instruction sheet" for carrying out this work on the 3.0TFSI engine - maybe ask a local Audi main dealer what their take is on this as any engine specific workshop procedure approved by Audi Germany should have been circulated round all dealers.
 
Talking to my dealer is like pulling teeth, you try and talk to them on the phone they just want to book it in to look at it.
 
Talking to my dealer is like pulling teeth, you try and talk to them on the phone they just want to book it in to look at it.

From the Audi, or any other main dealer's point of view I can understand them taking that line, as it could just be someone trying to get info from them and then getting somewhere else, or themselves to do the work. Also there is the unfortunate possibility that a customer asks them for a diagnosis over the phone, they agree to do the work, but when the car gets into the workshop there is another problem.

Maybe ask Audi UK about this workshop procedure, then go into your main dealer when you have some official Audi sourced info as then they need to play the party line.

Edit:- just to add "book it in and we will have a look at it" is all I've/I'd expect from an inquiring phone call, dealers can't seem to discriminate between a genuine "general" question and a request for help to an unknown problem. From asking the "carbon clean" question, I too would expect that a proper dealer's service desk to be able to give a true answer!
 
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I remember seeing something called terraclean on wheeler dealers, supposed to be good. Might be worth looking into
 
I remember seeing something called terraclean on wheeler dealers, supposed to be good. Might be worth looking into

To date, I think, procedures like "Terraclean" only work as intended on indirect injection engines as the cleaning fluid is used instead of the vehicle fuel. What a direct injection engine suffers from is coking of the inlet tract and that need cleaning, on a direct injection engine, by another process, maybe by blasting that area with ground up coconut shells.
 
Pulled some images off google to show the difference between the 3.2 FSI & 3.0 TFSI with regards to carbon build up.

3.2
AUDIA532FSI68000KM


3.0 TFSI 43,000 miles
Nyme7u7e


As you can see,the TFSI has considerably less carbon build up over a similar milage than the non boosted variety

And if you compare then to the 4.2 FSI the difference is massive

B8 S5 V8 Carbon Clean Before After JHM


Short journeys & driving like Miss daisy will cause more issues.

Rev em high n get em hot :)
 
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Carbon Doctor seem to sort things out, I'll need to have a look at what they do - probably get they take the charger off and blast away with a softish medium like crushed coconut shells.

Edit:- I was wrong, it is walnut shells they use!
 
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It looks like Carbon Build up may finally be a thing of the past with the newer CREC 3.0 TFSI.
Audi have added a secondary fuel injector system into the intake, thereby using petrol to clean the inlet tract like the good old days.
This has been done specifically to meet the latest emissions requirements however, not to address the carbon build up problems I suspect.
 
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I'm tempted to get mine done.
Had the supercharger off the other day to replace the pcv valve. That's a job and a half.
The ports were really black, but it has been through a lot of oil, even in the few months I've owned it.
Being the A6 version means it's not as tuned as yours, but think the walnut shell clean would be best.
 
I have done a fair bit of research since starting this thread.

Spoke to engine builders and numerous engine cleaners, these are my findings.

As the product tester for the owners club, I'm always testing something. Some months it feels like I do as many miles on a Dyno as on the road.

There seems to be a few ways advertised of removing carbon.

Putting some gas or fluid through the intake.

This is the one I have questions with, they make some bold claims. Regain lost power, better fuel. So what better person to test. I offered a bore scope my car, Dyno run it have it cleaned and repeat the process. I have made this offer to countless operators with not one taking me up on my offer.

Being involved the motor trade all my live and my father before me. I have seen my fair share of carbon removals, I takes grinding or blasting. So while I have no doubt in the various blasting processes, I have serious doubts on the chemical process. Now the chemical process does more then likely remove some contaminants, can not see carbon being one.

Where you have people swearing they felt a diferance after, could be some gunk removed or the placebo effect.

Even someone like myself that tests all day everyday, have to check placebo effect. If you get told this will change abc on your car. You are now paying extra attention to abc. Abc will feel different, I get someone else to double check any findings I'm unsure of.

In summing up
Gasfluid clean .... may clean something but not carbon. Cleaners have said it's more ptoventitive then reactive, they also admit running premium feul will have the same effect.

Blasting with media ... proven results
 
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Sea foam seems to remove the tiniest amount so not worth it IMO
 
The garage I use does the walnut blasting, I enquired last time I was in and they said they haven't done a 3.0 yet but have done plenty of V8 rs4's and s5's.

I asked if they could check the valves with a borescope but unfortunately due to the supercharger they don't think I would be possible. They said the only way to see if it needs doing is to remove the supercharger, by which point your going to be into a few hours labour and it may not need doing.

Off the top of my head I think they said to have it cleaned I'd be looking at £700-£800 so I passed on it for now.

The only way I'd really be having it done would be if they were replacing the charge pully as it would save putting it in the service position. You could also change the 'lifetime' oil in the charger while it was off so that would also be a bonus.

Ryan
 
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My SC has been off a few times.
 
Ill add my 2p.

Unless its actual media blasting to remove the deposits, walnuts or whatever they use. Then NO chemical formula run through the cars fuel system is going to remove any deposits...and certainly not over a 30minute period your car runs on terraclean or whatever rubbish it is these days.

Terraclean, or any other additive cleaner is just a huge marketing spin and ultimately a con. What happens to the carbon deposits that come off intake valve side and have to travel across pistons, through turbos etc before coming to rest against a CAT converter or DPF in the exhaust.
 
I have done a fair bit of research since starting this thread.

Spoke to engine builders and numerous engine cleaners, these are my findings.

As the product tester for the owners club, I'm always testing something. Some months it feels like I do as many miles on a Dyno as on the road.

There seems to be a few ways advertised of removing carbon.

Putting some gas or fluid through the intake.

This is the one I have questions with, they make some bold claims. Regain lost power, better fuel. So what better person to test. I offered a bore scope my car, Dyno run it have it cleaned and repeat the process. I have made this offer to countless operators with not one taking me up on my offer.

Being involved the motor trade all my live and my father before me. I have seen my fair share of carbon removals, I takes grinding or blasting. So while I have no doubt in the various blasting processes, I have serious doubts on the chemical process. Now the chemical process does more then likely remove some contaminants, can not see carbon being one.

Where you have people swearing they felt a diferance after, could be some gunk removed or the placebo effect.

Even someone like myself that tests all day everyday, have to check placebo effect. If you get told this will change abc on your car. You are now paying extra attention to abc. Abc will feel different, I get someone else to double check any findings I'm unsure of.

In summing up
Gasfluid clean .... may clean something but not carbon. Cleaners have said it's more ptoventitive then reactive, they also admit running premium feul will have the same effect.

Blasting with media ... proven results

http://www.a5oc.com/forums/audi-a5-s5-tech/97929-ive-got-into-engine-3.html

Check post #70.

I was skeptical, but it was Cuppa (might know him from his S5 build on here, although he doesn't seem that active on here or over on A5OC anymore) who got involved with this carbon clean company. Several members had it done, and this one chap had it on a dyno before and after the carbon clean process.

As you can see, some objective gains in BHP, so its clearly doing something...?

Now you could argue that walnut blasting and the like will clean much more, but how much more effective would it be in terms of regaining lost BHP? If you consider the cost difference is £99 vs. £900 to even the thousands £££, I find it hard to believe that it will have up to 10x the effectiveness....

Now will walnut blasting be more beneficial for other components that are prone to failure due to carbon build up...possibly, but I agree, its a shame no company is willing to let you test all aspects objectively. Shame Cuppa isn't still active, as I imagine he would be more than happy (assuming he's still involved with them...).

For me personally, I was active when Cuppa was and have no reason to think he would sell me, or any other A5OC member snake oil if he knew it didnt do anything. Based on feedback from other users (I also met the guy who had it dyno'd and his car, so have no reason to disbelieve his post) I would happily pay £99 if I were to have a car with suspected carbon build up. Would even incorporate it with my routine maintenance along with oil changes given the price...
 
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DrEskimo, Thanks for your post, however the S5 in that example has the N/A V8 FSI which suffers really badly with carbon buildup, caused by the large valve overlap at lower speeds, so any sort of cleaning would help. See photos further up this thread.
You can see the before figures are poor.
The V6 3.0 TFSI Engine is supercharged and suffers much less (if at all).
 
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DrEskimo, Thanks for your post, however the S5 in that example has the N/A V8 FSI which suffers really badly with carbon buildup, caused by the large valve overlap at lower speeds, so any sort of cleaning would help. See photos further up this thread.
You can see the before figures are poor.
The V6 3.0 TFSI Engine is supercharged and suffers much less (if at all).

Yea fair enough. Obviously any carbon clean process will just restore what's lost due to carbon build up.

My post was to just provide some objective evidence that carbon clean did have a measurable effect on restoring lost horses.


Sent from my iPhone using Tapatalk
 
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Yea fair enough. Obviously any carbon clean process will just restore what's lost due to carbon build up.

My post was to just provide some objective evidence that carbon clean did have a measurable effect on restoring lost horses.
Yes fair enough. £99 for 21bhp is very worthwhile and obviously some of the softer "sludge" must have been removed.
However the V8 is still 17bhp DOWN on Audi's quoted figures, after cleaning.
By comparison, my V6 TFSI after 82k mls was 15bhp UP on Audi's quoted figures without any cleaning or other modifications. (Assuming both Dyno's are calibrated similarly).
I feel that cleaning would have little effect on my engine in removing the hardened deposits. [other than the walnut shell method].
I conclude that anyone with a B8 N/A V8 should get their engine cleaned as you have shown it to be worthwhile.
 
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