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32k miles intake valve carbon buildup

16K views 41 replies 12 participants last post by  JohnInNH 
#1 ·
Just cleaned my intake valves this weekend and wanted to share.
 
#2 ·
How about some details? Pictures? That would be more helpful.
 
#3 · (Edited)
Missed attachments. The last pic was after cleaning. 2018 3.0t 32k miles. There was some oil residue inside the intake manifold from the pcv. The throttle bodies were very clean.
 

Attachments

#7 ·
Are you stock? Any mods? What fuel?
 
#8 ·
I will say that it did make a noticeable difference. I did have slight stumbling at idle, especially when cold, which is gone now. And acceleration feels more responsive.


It took about about six hours for me to complete.You can't see it but there was considerable buildup on the back side of the stems. I used a couple of pick tools to scrape off. Then I followed up with walnut blasting using an adapter I got off ebay.
 
#13 ·
I have always had the BG Intake Cleaning Service done to my DI cars. Cost around $150 and cleans out the throttle body, intake and valves. They say to do it every 30K miles. I know there are chems you can buy like Seafoam, etc. that do this as well but they are not nearly as efficient and do not clean as well as the professional BG service as BG atomizes and mists under pressure. Just a thought for those that may be interested.

https://www.bgprod.com/services/gasoline-fuel-services/gdi-fuelair-induction/
 
#14 ·
I have always had the BG Intake Cleaning Service done to my DI cars. Cost around $150 and cleans out the throttle body, intake and valves. They say to do it every 30K miles. I know there are chems you can buy like Seafoam, etc. that do this as well but they are not nearly as efficient and do not clean as well as the professional BG service as BG atomizes and mists under pressure. Just a thought for those that may be interested.

https://www.bgprod.com/services/gasoline-fuel-services/gdi-fuelair-induction/

That's appears worthwhile as it doesn't cost much. The carbon on the valves was relatively soft and easy to remove. I have done carbon removal on pistons before and that crap was practically one with the piston.
 
#18 ·
I ran CRC GDI cleaner through my engine at about 21k miles. There was some interesting crap coming out of the exhausts from that. Obviously, this is no substitute for a mechanical cleaning, but I was hoping that possible regular use will mitigate build up.
 
#19 ·
I just passed 20k miles and would like to do the same. Did you spray the CRC GDI cleaner through the air intake box? And do we have to use two cans (i.e. one can per intake)? Sorry if this seems like a silly question.
 
#30 ·
#29 ·
Thought that was the hose AMS said not to mess with.


Anyways, if both banks have oil on them then there is a considerable amount of oil to be caught on the other side as well. I remember Scary initially installed the OCC there but got nothing. I guess I should take the time to clean the other side.
 
#35 ·
Earlier this year (pre-Covid), Valvoline got a race car driver, a mechanic and a boroscope, and inspected random driver's cars for intake valve build-up:



As for answers to the questions - Valvoline Modern Engine 5W30, Mishimoto Catch Can, Ecutek, spirited, 1st owner.
 
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#38 ·
This reminds me that I still haven't opened the snake cam I bought two years ago. This procrastination thing is like a cancer - thanks to Mr. PHead.
 
#36 ·
So what's with this Kaydro Technologies guy? One post asking a list of questions 2 months ago and is never seen again.

I guess when he said they lead the pack, they didn't specify in which direction.
 
#37 ·
So what's with this Kaydro Technologies guy? One post asking a list of questions 2 months ago and is never seen again.

I guess when he said they lead the pack, they didn't specify in which direction.
Kareem is probably too busy with his YT channel.
 
#41 ·
Yup. It's kinda like - trust us, it will do its job because otherwise it will look like this, and cause these "x" problems.

I've used their Modern Engine Oil for just over 15k miles (three oil & filter changes). Sure, I admit I drank the Valvoline Kool-Aid and changed to ME because it professed less carbon build-up on the valves, but what really impressed me was the outstanding UOA results (i.e., for wear metals) and how it held up in the engine toward the end of the 5k OCI (i.e., didn't turn black, as it has a good mix of detergents and dispersents to handle soot). Fuel Dilution and Soot (Accumulation) in the oil are the chief by-products of Direct Injection.

If I get less carbon build-up using ME, it's an added bonus.
 
#42 ·
Answers to the questions - Valvoline Modern Engine Oil-> 0W20, Mishimoto Catch Can, Ecutek tuned, spirited, 1st owner, 32000 miles. Oil change interval = 4,000 miles. Blackstone oil analysis on every oil change.
 
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