# Intake Valve Carbon Buildup



## robertdaleweir (Sep 28, 2005)

I own a 2017 Tiguan R-Line model which has the 2.0 Liter Gasoline Engine in it. My son has told me that these engines used to have a issue with carbon buildup on the intake valves and I am wondering if that would still be true for my specific vehicle. See attached. I believe the attached is referring to the engine in my vehicle. Apparently VW has upgraded its systems and this issues may not be an issue for me. Any help would be welcome ...
Robert


----------



## twiggs462 (Mar 20, 2007)

Without MPI (Multi Port Injection) carbon build up is an issue. Change your oil often, use good oil. Use top tier fuel, drive spirited once in a while.


----------



## RatBustard (Jun 15, 2007)

it's still an issue and you'll eventually need a carbon cleaning, like all DI engines without additional port injection.


----------



## Leirk (Oct 1, 2020)

Yes your DI engine is going to be subject to intake valve carbon buildup like all others. Don’t sweat it until it’s an issue! I made 195k miles on my 1.4 before cold start misfires.


----------



## jonese (Jun 21, 2020)

I think VW actually said they have reduced the amount of carbon buildup on more modern engines.

Your still going to need it at some point, hopefully later than sooner. IMHO, It's not really a show-stopper type of problem, think of it more of a maintenance item.


----------



## WishingBig (Jan 23, 2012)

this was my 12 golf r with 125k miles I’ve only owned it since 100k miles. Carbon cleaning shouldn’t be ignored.


----------



## robertdaleweir (Sep 28, 2005)

jonese said:


> I think VW actually said they have reduced the amount of carbon buildup on more modern engines.
> 
> Your still going to need it at some point, hopefully later than sooner. IMHO, It's not really a show-stopper type of problem, think of it more of a maintenance item.


Would an Air/Oil separator (after market) be a way to lessen the carbon build up?


----------



## robertdaleweir (Sep 28, 2005)

RatBustard said:


> it's still an issue and you'll eventually need a carbon cleaning, like all DI engines without additional port injection.


OK, Is an inline Air/Oil separator after market device worth using in your opinion?


----------



## robertdaleweir (Sep 28, 2005)

Leirk said:


> Yes your DI engine is going to be subject to intake valve carbon buildup like all others. Don’t sweat it until it’s an issue! I made 195k miles on my 1.4 before cold start misfires.


I have heard it is a >$1k repair and I am not sure it is a DIY type of job?


----------



## robertdaleweir (Sep 28, 2005)

twiggs462 said:


> Without MPI (Multi Port Injection) carbon build up is an issue. Change your oil often, use good oil. Use top tier fuel, drive spirited once in a while.


Ok. Yes I do all of the things you mention. Filter and oil every 5,000 km and only use high test gas. What are your thoughts on Air/Oil separator after market attachments?


----------



## robertdaleweir (Sep 28, 2005)

WishingBig said:


> this was my 12 golf r with 125k miles I’ve only owned it since 100k miles. Carbon cleaning shouldn’t be ignored.


Wow that sucks. Is it a DIY type of job to clean that off?


----------



## jonese (Jun 21, 2020)

It can be DYI if you can rent the tools. It's mostly a labor operation.


----------



## WishingBig (Jan 23, 2012)

It was a pain for me but I wouldn’t have even thought to do so if it wasn’t for needing to change a knock sensor.. it took me all day with rags, brushes and intake cleaner. Some day I might invest in a walnut blaster


----------



## Krautwagen (Sep 17, 2002)

With the 2018+ B-cycle engine, I would expect reduced carbon fouling due to the intake valves closing prematurely at part load. This is assuming the main cause of the fouling is backflow during the reduced velocity portion of the intake stroke, and not carbon depositing during higher velocity flow periods earlier in the intake stroke or during intake/exhaust valve overlap.


----------



## RatBustard (Jun 15, 2007)

Krautwagen said:


> With the 2018+ B-cycle engine, I would expect reduced carbon fouling due to the intake valves closing prematurely at part load. This is assuming the main cause of the fouling is backflow during the reduced velocity portion of the intake stroke, and not carbon depositing during higher velocity flow periods earlier in the intake stroke or during intake/exhaust valve overlap.


I'm not a combustion engineer, but most build up on DI engines is related to PVC operation (crankcase gases) and stem seal leakage. a bad or poorly designed PCV will put too much oil into the intake and it doesn't get washed off the valves from port injection, and burns/builds up. same with stem seal leakage: too much leakage can deposit oil and result in build up. 

not sure how much overlap and what the timing is on the B-cycle but I can't imagine it's a remarkable difference from any other DI engine at this point.


----------



## 1915cc (Apr 23, 2018)

robertdaleweir said:


> I have heard it is a >$1k repair and I am not sure it is a DIY type of job?


it’s not anywhere near 1k repair, I had mine done at the VW dealer when my water pump was changed, it was about $275.00


----------



## Remzac (Nov 25, 2007)

Are the catch cans a placebo or are they a product that works? Like this one?
Universal ECS Tuning Baffled Oil Catch Can Kit (8oz) 


2019 Volkswagen Tiguan 4Motion


----------



## jonese (Jun 21, 2020)

1915cc said:


> it’s not anywhere near 1k repair, I had mine done at the VW dealer when my water pump was changed, it was about $275.00


Yea, $1000 seems a bit high, but yours is low as they were already in there with the manifold removed.

Standalone work, you're probably looking at 2 to 2.5 times that price.

IMHO, it's not something I would get the dealer to do unless they were in there for some other warranty work at the same time. Either DIY or euro independent shop.


----------



## robertdaleweir (Sep 28, 2005)

Remzac said:


> Are the catch cans a placebo or are they a product that works? Like this one?
> Universal ECS Tuning Baffled Oil Catch Can Kit (8oz)
> 
> 
> 2019 Volkswagen Tiguan 4Motion


Yes the very one you show in your URL. Are they quite good?


----------



## Remzac (Nov 25, 2007)

robertdaleweir said:


> Yes the very one you show in your URL. Are they quite good?


So they in essence work to eliminate carbon build up. Sweet. I may get one...

2019 Volkswagen Tiguan 4Motion


----------



## jonese (Jun 21, 2020)




----------



## robertdaleweir (Sep 28, 2005)

jonese said:


> It can be DYI if you can rent the tools. It's mostly a labour operation.
> 
> Sent from my ONEPLUS A6013 using Tapatalk


Ok. I am a ways off from having it manifest but just trying to be a bit proactive. I would put the Universal ECS Tuning Baffled Oil Catch Can Kit (8oz) on now if it could save me down the road. Ounce of prevention thing ...


----------



## jonese (Jun 21, 2020)

Keep in mind that in cold climates it might freeze up.


----------



## Remzac (Nov 25, 2007)

After watching the video I don't think it's a good idea up here in Alberta. Too cold all winter long. Looks to be great for none freezing regions.

2019 Volkswagen Tiguan 4Motion


----------



## jonese (Jun 21, 2020)

Remzac said:


> After watching the video I don't think it's a good idea up here in Alberta. Too cold all winter long. Looks to be great for none freezing regions.
> 
> 2019 Volkswagen Tiguan 4Motion


Agreed! It was - 35C for a while in Calgary last year.


----------



## Remzac (Nov 25, 2007)

jonese said:


> Agreed! It was - 35C for a while in Calgary last year.


Same up in Edmonton

2019 Volkswagen Tiguan 4Motion


----------



## TIGSEL (Dec 22, 2011)

Just do this every 40-50k miles and you should be good: https://www.walmart.com/ip/CRC-05319-GDI-IVD-Intake-Valve-Turbo-Cleaner-11-oz/173095958?wmlspartner=wlpa&selectedSellerId=0&adid=22222222222000000000&wmlspartner=wmtlabs&wl0=e&wl1=s&wl2=c&wl3=10352200394&wl4=pla-1103028060075&wl5=&wl6=&wl7=&wl10=Walmart&wl11=Online&wl12=173095958_0&wl14=crc dgi cleaner&veh=sem&msclkid=a407716da0bf1d4c1f511056392df45e&gclid=a407716da0bf1d4c1f511056392df45e&gclsrc=3p.ds








Been using this for years with great success.


----------



## PLF8593 (Feb 11, 2014)

robertdaleweir said:


> I have heard it is a >$1k repair and I am not sure it is a DIY type of job?


it is about $3-400. It’s DIY if you have a media blaster and the tools/skills to remove the intake manifold.

no, the air/oil separator won’t help


----------



## MLB123 (Jan 19, 2021)

robertdaleweir said:


> I own a 2017 Tiguan R-Line model which has the 2.0 Liter Gasoline Engine in it. My son has told me that these engines used to have a issue with carbon buildup on the intake valves and I am wondering if that would still be true for my specific vehicle. See attached. I believe the attached is referring to the engine in my vehicle. Apparently VW has upgraded its systems and this issues may not be an issue for me. Any help would be welcome ...
> Robert


Yes it is something that you will eventually have to do. I had mine done a couple of weeks ago at 70,xxx miles and it was pretty gooped up. I wasnt having any issues with it, just decided to go ahead and get it done as PM. Ive heard that the average time is between 75,000-100,000 miles. It has made quite a bit of difference in responsiveness and my gas mileage is a little better. My mechanic told me that using top tier oils and gasoline helps alot but there's no "fix" for the problem. I think VW has gone to a port/direct injection setup in some of their new cars but am not 100% sure about it. Here is a pic of my least gunked up one.....


robertdaleweir said:


> I own a 2017 Tiguan R-Line model which has the 2.0 Liter Gasoline Engine in it. My son has told me that these engines used to have a issue with carbon buildup on the intake valves and I am wondering if that would still be true for my specific vehicle. See attached. I believe the attached is referring to the engine in my vehicle. Apparently VW has upgraded its systems and this issues may not be an issue for me. Any help would be welcome ...
> Robert





robertdaleweir said:


> I own a 2017 Tiguan R-Line model which has the 2.0 Liter Gasoline Engine in it. My son has told me that these engines used to have a issue with carbon buildup on the intake valves and I am wondering if that would still be true for my specific vehicle. See attached. I believe the attached is referring to the engine in my vehicle. Apparently VW has upgraded its systems and this issues may not be an issue for me. Any help would be welcome ...
> Robert


----------



## tsisson3 (Jan 28, 2020)

robertdaleweir said:


> OK, Is an inline Air/Oil separator after market device worth using in your opinion?


I pull quite a bit of oil and water out on my GTI, for me it has been good.


----------



## 2wheelgnr (Mar 23, 2021)

Any good enough snake oil injector cleaner you can put in gas maintenance wise to help get a lil help with keep it clean??? or pro-longing until you need it done...or like a seafoam treatment every couple 5-6 years???


----------



## Remzac (Nov 25, 2007)

2wheelgnr said:


> Any good enough snake oil injector cleaner you can put in gas maintenance wise to help get a lil help with keep it clean??? or pro-longing until you need it done...or like a seafoam treatment every couple 5-6 years???


No

2019 Volkswagen Tiguan 4Motion


----------



## TIGSEL (Dec 22, 2011)

2wheelgnr said:


> Any good enough snake oil injector cleaner you can put in gas maintenance wise to help get a lil help with keep it clean??? or pro-longing until you need it done...or like a seafoam treatment every couple 5-6 years???


In DI engines gasoline does not touch the valves, therefore nothing you put in your gas will help keeping your valves clean. One thing you can do is to use oil with lowest NOACK rating possible. It will slow down the process but not eliminate it. Do the CRC treatment every 40-50k and you'll never have to worry about carbon buildup again.


----------



## 2wheelgnr (Mar 23, 2021)

Oh thats right..you guys have said before in this thread over and over that gas doe not touch the valves like "normal" widely used engines....DUH...........so no gas additive will help..... sorry for being thick but thats all makes complete sense......


----------



## Phaeton4me (Jul 24, 2017)

So, as pointed out direct injected engines do not have fuel sprayed ahead of the valves which would clean the intake to some degree since gasoline is a solvent. Compounding the issue is the fact that there is internal EGR utilizing valve timing overlapping the intake and exhaust valve open time for emission purposes. I have had to mechanically clean the intake ports, divider plates and valves on my 2010 CC twice which was performed in conjunction with intake manifold replacement due to implausible intake flap codes. Second go round deferred until water pump housing cracked catastrophically dumping coolant. Had a slow coolant leak, expected pump to be the issue had everything necessary to do that but pump was actually good at 175k. Intake manifold has to come off to get to it anyway..... good plan on my part actually. Took multiple rounds of unanticipated parts orders that added weeks to job duration but ok since I had 7 other cars to drive. Atypical for most. Strong engine but every 80-120k miles issues with manifold flap or carbon buildup requires service. Fortunately I can do it all myself rather than rely on dealership or other shop. So, what do owners actually save on better fuel mileage when routine expensive repairs are necessary every 100k? Of course all manufacturers are faced with this.... the 2.0 CC with 6 speed manual does drive like a bat out of hell though...........


----------



## green_gti (Jul 20, 2002)

robertdaleweir said:


> Would an Air/Oil separator (after market) be a way to lessen the carbon build up?


I just had the carbon removed from my R at 86K. It's expensive but necessary. 
It definitely would eliminate the buildup. 
I just took delivery of an APR Catch-can. But, I haven't been able to install it yet because it's been blazingly hot here in the part of Southern California that I live in. Also, I have worries that CALARB will think that the Catch-Can is disabling part of the emission control on the automobile, which we know that it doesn't, but there are some pretty small-minded people in that organization.


----------



## green_gti (Jul 20, 2002)

jonese said:


> Keep in mind that in cold climates it might freeze up.


If you are worried about water freezing in the Catch-Can, look at the APR Catch-Can. It has a valve on the bottom to drain the Catch-Can. I will be adding a Tygon hose from Lowe's to the valve in order to drain it out without having to put a cup or bottle underneath with the engine hot, just an aluminum roaster pan under the car to catch what comes out of the Catch-Can.


----------



## ckspeed68 (Aug 20, 2012)

take a look at this thread in regards to "oil catch can" Oil Catch Can Post #7.


----------



## Smokenshot (Nov 22, 2019)

robertdaleweir said:


> I own a 2017 Tiguan R-Line model which has the 2.0 Liter Gasoline Engine in it. My son has told me that these engines used to have a issue with carbon buildup on the intake valves and I am wondering if that would still be true for my specific vehicle. See attached. I believe the attached is referring to the engine in my vehicle. Apparently VW has upgraded its systems and this issues may not be an issue for me. Any help would be welcome ...
> Robert





2wheelgnr said:


> Any good enough snake oil injector cleaner you can put in gas maintenance wise to help get a lil help with keep it clean??? or pro-longing until you need it done...or like a seafoam treatment every couple 5-6 years???


The gas is injected AFTER the valves so any gas additive would be minimal at best...


----------



## vwbaseball (Aug 2, 2005)

2wheelgnr said:


> Any good enough snake oil injector cleaner you can put in gas maintenance wise to help get a lil help with keep it clean??? or pro-longing until you need it done...or like a seafoam treatment every couple 5-6 years???


At around 100,000 miles my 2006 GLI started exhibiting intermittent coldstart misfires. At that point I started using 4 oz. of Lucas fuel treatment with every fill-up. I don't remember exactly how many fill-ups were required, but the misfires gradually became more infrequent until they disappeared altogether (knock on wood). I'll guess that it took maybe 10 fill-ups before the misfires disappeared completely. I'm a snake oil skeptic from way back, but you can't argue with success. So I continue the regimen. The car now has 160,000+ miles.


----------



## Puckster (Feb 26, 2011)

Find a shop that has one of these. 
Carbon Cleaning Machine | ATS Chemical
SImple half hour procedure. The over counter products don't work is they never make it to the intakes.. it all goes out the exhaust. This product also helps regenerate the catalytic converter. It sounds too good to be true but I have seen it up close. There are some great before and after shots.


----------



## TIGSEL (Dec 22, 2011)

Puckster said:


> Find a shop that has one of these.
> Carbon Cleaning Machine | ATS Chemical
> SImple half hour procedure. The over counter products don't work is they never make it to the intakes.. it all goes out the exhaust. This product also helps regenerate the catalytic converter. It sounds too good to be true but I have seen it up close. There are some great before and after shots.


CRC GDI cleaner works great. It's a150X concentrate and introduces directly into the intake. It does come out of the exhaust but not without cleaning valves first. Someone in Tiguan forum took before and after pictures of the valves, and they looked like new.


----------



## robertdaleweir (Sep 28, 2005)

TIGSEL said:


> CRC GDI cleaner works great. It's a150X concentrate and introduces directly into the intake. It does come out of the exhaust but not without cleaning valves first. Someone in Tiguan forum took before and after pictures of the valves, and they looked like new.


Hi TIGSEL
I have heard that using the GDI cleaner can damage the Catalytic Converter. Is that at all possible?
Robert


----------



## TIGSEL (Dec 22, 2011)

robertdaleweir said:


> Hi TIGSEL
> I have heard that using the GDI cleaner can damage the Catalytic Converter. Is that at all possible?
> Robert


CRC says it's safe for cats. I've used in on 3 of mine VWs and my cousin's GTI, so far no problems at all.


----------



## Remzac (Nov 25, 2007)

I just don't get how CRC GDI Cleaner cleans up the back side of the valves if the injectors squirt fuel into the combustion chamber directly. 

2019 Volkswagen Tiguan 4Motion


----------



## RatBustard (Jun 15, 2007)

Remzac said:


> I just don't get how CRC GDI Cleaner cleans up the back side of the valves if the injectors squirt fuel into the combustion chamber directly.
> 
> 2019 Volkswagen Tiguan 4Motion


CRC GDI Cleaner is not added to the fuel tank - you spray it into the throttle body while running the engine. 









CRC Industries | Global Supplier of Chemical Specialty Products


CRC manufactures over 1300 chemical products for Automotive, Marine, Heavy Truck, Hardware, Electrical, Industrial and Aviation markets.




crcindustries.com


----------



## Remzac (Nov 25, 2007)

RatBustard said:


> CRC GDI Cleaner is not added to the fuel tank - you spray it into the throttle body while running the engine.
> 
> 
> 
> ...


Ahhh

2019 Volkswagen Tiguan 4Motion


----------

