Top End Decoke?

[Graemetee]

I've noticed recently that my 97,000 mile Tfsi isn't running as well as it has in the past and I'm wondering whether or not it's worth getting the head decked after reading a few things on here about it.

I've noticed that the walnut blasting seems to be popular with some people so I might look into getting it done.

Has anyone had their car done and did it make much of a difference?

Can anyone recommend somewhere in the Surrey/Berkshire area to get this done?

 

[Marc B7]

Get it done asap!

I am in the process of doing mine myself today. My car is on 38000 miles and i am disgusted at how bad it is for a low mileage car.

There was about a mug of oil inside the passenger side intercooler and the crud on the valves was really bad too.

All cleaned now and i am in the process of putting it all back together today.

 

[Graemetee]

That sounds like some of the photo's I've seen so far of peoples valves all coked up.

Is it a big job removing the manifold to get at the valves?

 

[Marc B7]

It's not a big job as long as long as you have the correct tools.

I followed this guide:
http://www.stasisengineering.com/sites/default/files/install_pdfs/STaSIS MTF turbo install longitudial.pdf

On that guide goto page 28 "fuel injector replacement" all the info on how to remove the inlet manifold is there.

 

[Marc B7]

Here are some of my valves yesterday @ 38000 miles:

And this is how that look after cleaning:

 

[Graemetee]

So what did you clean them with?
Was it just carb cleaner and a wire brush?

 

[Marc B7]

This is what I used, all bought from eBay:

Working on one valve set at a time I made sure the valves were in the closed position.

To start I used the wax carving set to scrape out as much crud as possible.

I then added some ISC liquid and let it sit.

With a little ISC sitting in the valves I used the white plastic brushes attached to my drill (set to low speed) to remove the baked on deposits.

I used lots of paper towels to mop out the black gunk and ISC and then repeated the above steps several times until clean.


Cleaning took roughly 30 mins per valve set.

Also eye protection and rubber gloves on at ALL times as ISC is really nasty stuff

 

[Marc B7]

I also gave the tumble flaps and the complete inlet manifold a good clean out too as they were covered.

 

[gary_a4_quattro]

Here are some of my valves yesterday @ 38000 miles:

And this is how that look after cleaning:

I'm really surprised how gunked up they have become, especially as you say, at 38 K !!! Great job on the clean up, Marc

So, I guess the $1,000,000 question is " how to prevent a reoccurance of the crap n gunk build up....... Is deleting the PCV system and going to a catch can the answer ? "

I'm thinking this is probably a job I should be doing before the car goes for its remap, just feel I wouldn't be getting the best of R-Techs efforts if mine is carrying around that much deposited carbon in the inlet system !

 

[Graemetee]

It'll be interesting to hear how the car goes after the clean-up.

 

[gary_a4_quattro]

It'll be interesting to hear how the car goes after the clean-up.

Absolutely Graeme, all that design time engineers have spent on getting a smooth airflow, with the right swirl pattern, to aid fuel mixing into the combustion chamber isnt gonna be helped by all that build up.

 

[Graemetee]

Absolutely Graeme, all that design time engineers have spent on getting a smooth airflow, with the right swirl pattern, to aid fuel mixing into the combustion chamber isnt gonna be helped by all that build up.

And the next problem of course is how do we stop it happening again?
If I'm doing it myself, I don't much fancy having to pull off the inlet manifold and do it every few thousand miles.

 

[Marc B7]

I'm thinking this is probably a job I should be doing before the car goes for its remap

That is why i am doing mine now I am prepping it for mapping.

I have just fitted a front intercooler and found a mug full of black oil in the passenger side intercooler. Then i pulled the inlet manifold and found the build up.

 

[S3Alex]

A full PCV delete and vent to atmosphere catch can system will cure it.
It's not a cheap solution but Integrated Engineering make a very good setup and that's what I use.

 

[Marc B7]

A full PCV delete and vent to atmosphere catch can system will cure it.
It's not a cheap solution but Integrated Engineering make a very good setup and that's what I use.

After a lot of reading I don't see any real solution of curing the problem. Catch cans are a pain and require maintaining (i have a mocal on my turbo Corrado) nearly all tfsi "delete" kits have a passageway machined into them which will still send vapor to the turbo side thus sending oil residue to the intercoolers and back up to the inlet, unless you block the turbo pcv inlet off with a plate. You then risk blowing seals.

The only true solution is vent to atmosphere/exhaust with no catch can, but MOT and also the smell then becomes the problem.

Here is an interesting read:
http://www.audizine.com/forum/showthread.php/522378-The-ULTIMATE-PCV-Fix-Get-rid-of-Carbon-for-Good!

and also

http://www.audizine.com/forum/showthread.php/504787-PCV-Modification-and-Education-Thread

 

[S3Alex]

To be fair you do get a bit of an oily smell but its not bad.

Mine is a full VTA system.

 

[TOM.S]

That is why i am doing mine now I am prepping it for mapping.

I have just fitted a front intercooler and found a mug full of black oil in the passenger side intercooler. Then i pulled the inlet manifold and found the build up.

Hi Marc. do you by any chance have a link,or a write up for the front mount intercooler you got?
I'm thinking of making up a set up myself as i can find a decent kit to suit my car.
and would really appreciate any help advice regards the subject..

 

[Marc B7]

Hi Marc. do you by any chance have a link,or a write up for the front mount intercooler you got?
I'm thinking of making up a set up myself as i can find a decent kit to suit my car.
and would really appreciate any help advice regards the subject..

Bought mine from a member on here. It was tricky to fit, I had the relocate my power steering cooler, but it was super cheap and the way i mounted it i could keep my fog lights and plastic surrounds.

http://cxracing.eu/product-eng-304-...-B7-2-0T-28x7x2-5-Intercooler-2-5-In-Out.html

Install guide:
http://www.audizine.com/forum/showthread.php/419162-B7-A4-FMIC-Install-eBay-CX-Racing

 

[TOM.S]

Thanks.
Yes thats more or less what I'm after tho I don't mind keeping the oem coolers+ add a frontmount to them.
my biggest concern is to get a snug fit to keep the fogs/their covers and the problem with the map sensor on the pasenger side cooler.

 

[Marc B7]

I don't mind keeping the oem coolers+ add a frontmount to them.
my biggest concern is to get a snug fit to keep the fogs/their covers and the problem with the map sensor on the pasenger side cooler.

You cant keep the OEM coolers. There is a boss on the aluminium piping for the sensor to fit into.

 

[Graemetee]

This is what I used, all bought from eBay:

Working on one valve set at a time I made sure the valves were in the closed position.

To start I used the wax carving set to scrape out as much crud as possible.

I then added some ISC liquid and let it sit.

With a little ISC sitting in the valves I used the white plastic brushes attached to my drill (set to low speed) to remove the baked on deposits.

I used lots of paper towels to mop out the black gunk and ISC and then repeated the above steps several times until clean.


Cleaning took roughly 30 mins per valve set.

Also eye protection and rubber gloves on at ALL times as ISC is really nasty stuff

Do you have an eBay link to the brush set you used by any chance?

 

[Marc B7]

Do you have an eBay link to the brush set you used by any chance?

Here are all the parts I used:

BG ISC Cleaner.
I bought 2 but only 1 is needed.
http://www.ebay.co.uk/itm/GENUINE-B...516?pt=LH_DefaultDomain_3&hash=item2ed14339fc

12 Piece carving set.
http://www.ebay.co.uk/itm/12pc-Wax-...035?pt=LH_DefaultDomain_3&hash=item3aa6e91bd3

38 Piece hex drive brush set.
Or a small bottle brush/tooth brush will do but will take longer.
http://www.ebay.co.uk/itm/38pc-WIRE-BRUSH-SET-STEEL-BRASS-NYL-ON-1-4-HEX-DRIVE-/281624077689?

Inlet manifold gasket x1
Optional but worth changing for piece of mind. Mine looked ok but I changed it anyway.
http://www.ebay.co.uk/itm/INLET-MAN...188?pt=LH_DefaultDomain_3&hash=item2c7ee9850c

2.0 Tfsi Injector seal kit x 4
If your injectors pull out of the head as you remove the inlet manifold replace the teflon injector seals.
If the car is high mileage it is probably worthwhile replacing all of the injector seals and mounting hardware anyway.
http://www.ebay.co.uk/itm/GENUINE-A...131?pt=LH_DefaultDomain_3&hash=item4d1127be7b

 

[Marc B7]

Also if you don't already have some get yourself this:
http://www.ebay.co.uk/itm/Sealey-AK...152?pt=LH_DefaultDomain_3&hash=item5aeea7ae30

and this:
http://www.ebay.co.uk/itm/SEALEY-TR...714?pt=LH_DefaultDomain_3&hash=item2c831b1ef2

 

[ANDYTQ]

Mine was just as bad,i had the decoke /engine rebuild done @ badger 5,a 034 motorsport catch can was fitted and water/meth injection added to help keep the valves clean.Hopefully this will solve the issue.

 

[DrEvil]

Here are some of my valves yesterday @ 38000 miles:

[Pics Removed]

Wow, that is some serious build up for 38k miles! I wish I had the time to do this myself but think I will be engaging the assistance of a Audi specialist mobile mech who quoted quite a reasonable price to do this for me.

Good tip on getting the injector seals redone at the same time.

Is there a test that can easily be run to check that the injectors are running as they should be (in case any of them are on their way out then maybe worth looking at that at the same time)?

 

[Marc B7]

Update on my progress.
The car drives smother and seems to pick up better than before. I have not had chance to see if it affects mpg.


I also think I have found a good solution for excess oil collecting in the intercooler pipework:



Here is a custom install on an A4 B7
http://www.audizine.com/forum/showthread.php/600243-Installed-a-Mann-Provent-recently

Through some research, removing the oil using this MANN filter produces mainly dry sooty deposits on the valves (due to valve overlap, guide seals etc) instead of really oily nasty goop. This will greatly help with regular cleaning in the future. Reason being, Intake cleaner can then be sprayed into the inlet manifold while the engine is running and the dry deposits will better absorb the cleaning fluid, helping wash away deposits.

I will be installing this system over the coming weeks and monitoring the outcome, as my valves and intercooler are all clean at the moment.

 

[DrEvil]

Update on my progress.
The car drives smother and seems to pick up better than before. I have not had chance to see if it affects mpg.


I also think I have found a good solution for excess oil collecting in the intercooler pipework:



Here is a custom install on an A4 B7
http://www.audizine.com/forum/showthread.php/600243-Installed-a-Mann-Provent-recently

Through some research, removing the oil using this MANN filter produces mainly dry sooty deposits on the valves (due to valve overlap, guide seals etc) instead of really oily nasty goop. This will greatly help with regular cleaning in the future. Reason being, Intake cleaner can then be sprayed into the inlet manifold while the engine is running and the dry deposits will better absorb the cleaning fluid, helping wash away deposits.

I will be installing this system over the coming weeks and monitoring the outcome, as my valves and intercooler are all clean at the moment.

Good find, I hadn't seen that before.

I had looked at this one and thought this looked very neat, but the difficulty of reversing if you changed your mind put me off: http://www.audizine.com/forum/showthread.php/522378-The-ULTIMATE-PCV-Fix-Get-rid-of-Carbon-for-Good!

 

[CMC81]

Just posted a thread regarding my car, i couldn't recommend it enough.

 

[Marc B7]

I had looked at this one and thought this looked very neat, but the difficulty of reversing if you changed your mind put me off: http://www.audizine.com/forum/showthread.php/522378-The-ULTIMATE-PCV-Fix-Get-rid-of-Carbon-for-Good!

Yeah, posted about that one above.

Problem is Mr. MOT inspector would spot the welded in pipe and maybe be a little curious as to what it is. It would be ok if your on good terms with your local tester

Ive also heard some good things and some bad things about the exhaust vacuum mod, plus my avant's rear gets dirty enough as it is.

 

[DrEvil]

Yeah, posted about that one above.

Problem is Mr. MOT inspector would spot the welded in pipe and maybe be a little curious as to what it is. It would be ok if your on good terms with your local tester

Ive also heard some good things and some bad things about the exhaust vacuum mod, plus my avant's rear gets dirty enough as it is.

So do you know how much effort does the Provent need, i.e. how often does it need checking etc, the filter changing, is the oil really clean enough to filter back into the engine?

 

[Marc B7]

From what I have seen on other forums you can remove the filter and wash it in petrol/carb cleaner etc. and it will come up nice and clean. Only needs replacing if damaged/degrading.

As for checking intervals, I don't know.
I'm guessing that will very much depend on how you drive the car, the mileage of the engine and also if the engine is modified (more boost).
I would be giving it a clean at 5000 miles to start with and see how dirty it is, then go from there.

As for the oil/blowby/water that drains back to the sump, it might slightly increase the degradation of the engine oil, but I very much doubt anyone would notice any difference so long as your doing regular oil changes, top ups etc.

 

[DrEvil]

From what I have seen on other forums you can remove the filter and wash it in petrol/carb cleaner etc. and it will come up nice and clean. Only needs replacing if damaged/degrading.

As for checking intervals, I don't know.
I'm guessing that will very much depend on how you drive the car, the mileage of the engine and also if the engine is modified (more boost).
I would be giving it a clean at 5000 miles to start with and see how dirty it is, then go from there.

As for the oil/blowby/water that drains back to the sump, it might slightly increase the degradation of the engine oil, but I very much doubt anyone would notice any difference so long as your doing regular oil changes, top ups etc.

I have to say that does seem like one of the best solutions assuming you aren't going down the water meth etc route.

It'll probably be a while before I get round to doing anything like this on mine, so would be really interested in keeping tabs on your progress. I picked up a cheap small boroscope (<£10 and works off the usb port on my android phone) from amazon, attached it to a hanger for control - you could keep tabs on carbon build over time??

 

[Marc B7]

That is my plan, a small camera to have a look into the valve area. Has your camera got a light?

 

[DrEvil]

That is my plan, a small camera to have a look into the valve area. Has your camera got a light?

Yep comes with an adjustable light. Haven't had the time I need to take the throttle body off, so haven't tested if it is bright enough.

If you are close enough you can borrow mine to test. I'm in Herts.

 

[Marc B7]

Brecon Beacons, Mid Wales

 

[S3Alex]

I have to say that does seem like one of the best solutions assuming you aren't going down the water meth etc route.

Trust me.....WMI does NOT cure this issue.

I've had WMI for quite some time,programmed to begin at 0.5 bar,and top out at 2 bar,and it does not remove coke build-up on the inlet valves.

This was taken after running WMI between services,at 8000 mile intervals.



Obviously on highly tuned engines,the problem is likely to be worse,but it illustrates what goes on.


After blasting....




The problem is that even with sequential WMI port injection,it is not on for extended periods of time in everyday driving.

 

[DrEvil]

S3 Alex, I'm actually quite surprised that WM didn't noticeably help (though it makes sense in hindsight). In fact one of the reasons that I probably spend an hour a month considering it is because of one of your threads on the topic. Well, I'll definitely bury that thought!

 

[DrEvil]

Update on my progress.
The car drives smother and seems to pick up better than before. I have not had chance to see if it affects mpg.


I also think I have found a good solution for excess oil collecting in the intercooler pipework:



Here is a custom install on an A4 B7
http://www.audizine.com/forum/showthread.php/600243-Installed-a-Mann-Provent-recently

Through some research, removing the oil using this MANN filter produces mainly dry sooty deposits on the valves (due to valve overlap, guide seals etc) instead of really oily nasty goop. This will greatly help with regular cleaning in the future. Reason being, Intake cleaner can then be sprayed into the inlet manifold while the engine is running and the dry deposits will better absorb the cleaning fluid, helping wash away deposits.

I will be installing this system over the coming weeks and monitoring the outcome, as my valves and intercooler are all clean at the moment.

That audizine thread has been updated, it's proved to have its problems over the past year. Think the best solution for me is stock but regular checks for bust pcv or valve cover!

 

[S3Alex]

S3 Alex, I'm actually quite surprised that WM didn't noticeably help (though it makes sense in hindsight). In fact one of the reasons that I probably spend an hour a month considering it is because of one of your threads on the topic. Well, I'll definitely bury that thought!

You just have to think of how WMI works,and how long it runs for I think.

WMI is very useful for keeping temps down,and for raising knock limits,but it doesn't seem useful for this issue.

 

[Charlie Farley]

great write up on this problem, I am also a tad concerned about the state of mine to be honest.
I had a new engine (BUL) , but actually turned out to be a new short motor fitted a while back by audi under warranty, also a complete new turbo assembly , diveter valves etc etc, but its come to light after a somewhat heated conversation with them that they did as per warranty , fit a new short motor etc but refitted the the original head as it was not covered by the warranty, not a problem as it had covered less than 30k miles I thought, but as this carbon build up appears such a big and widespread problem with these engines I am a little concerned what the state of my valves etc are in, from my previous experiences with audi and my car I am not really overly impressed with the work that's been done.

I cant help thinking that they skiped any sort of decoking of the head and just refitted to the new block etc, and in which case as i'm on 51k miles now those valves etc are going to be really bad , especially based on the pics marc put up of his at 38k miles.

I have a great little remote cctv camera that will get right into the inlet ports but what is the easiest way of getting access to the port, only need to be one inlet , as if ones bad the remaining 3 will be the same.

I am thinking the same as above really and going with a vent to atmosphere pcv setup , if they are really nasty, and I think they may be as i'm seeing small amount of smoke again , its probably the only real way of dealing with the oil vapour getting back in .

any thoughts chaps.

rob