Valve Stem Carbon Build-up from Oil in DI Engines

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Brazil
Originally Posted by paoester
This will make you want to use a low saps oil!
But will that eliminate the problem? I'm not so sure...
 
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Colorado
Thread starter
Originally Posted by LeoStrop
Originally Posted by paoester
This will make you want to use a low saps oil!
But will that eliminate the problem? I'm not so sure...
Great question. I suspect its caused by higher saps levels, based on some engineering statements made over the years. You're right we can't be sure. It is speculated that Valvoline is putting some of its patented "Valvoline Premium Blue Restore" low aniline point oil patented chemicals in Valvoline Modern Engine oil. Although their Restore product mostly affects the ringlands on engines. https://www.bobistheoilguy.com/foru...arbon-cleaning-valvoline-premium-restore It dissolves carbon: https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/4995896/1 Several years ago Lubrizol thought valve deposits in DI engines were at least partly caused by ash combined with carbon, getting sticky. I'm not sure if they were ever right about it. They might be.
Originally Posted by Triple_Se7en
Too bad weren't shown a TGDI camera-shot, having 40-50K and using Modern Engine exclusively.
That would make it correct for sure. Maybe every 5 years we should run Valvoline Premium Blue Restore oil through the engine and see if that helps. Some would circulate via the PCV into the intake presumably from oil mist. Enough to do something up there.
 
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Atlanta,GA
About a decade ago someone around here provided a copy of a presentation from Lubrizol which stated the low-mid SAPS oils would not generate the same amount of carbon buildup.
 
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Southern NJ
In 2012 Mobil told me that is why they lowered the TBN and SA levels to .8. I would have loved to have seen the intake valves of my Mazda before I got rid of it as it only had M1 EP 0w20.
 
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My wife had a Mazda3 with a Skyactiv engine, hence my user name. She bought it new. The Mazda got it's best fuel economy when new and didn't do as good when it had over 20k on it. I think deposits on the intake valves played a role. The car still for great gas mileage regardless.
 
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WA
It's not a definitive solution but if I had a DI engine I'd invest in a catch can and regular intake cleanings. But how many avg consumers know about/want to be bothered with this, IV build up.
 
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222
Location
VA
Ive been learning alot from reading here lately about the DI engines and oil issues. How do you know if you have DI engine? My most modern vehicle is a 2012 4runner and Im assuming thats not DI.
 

pbm

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New York
While oil choice is obviously important in combatting carbon build-up....it's also obvious that DI was rushed to market before it was ready for prime time.
 
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Somewhere in time
What a bunch of malarkey. This is an assemblage of oohs and aahs along with an "authority" that tells them how bad it is. None of these cars are stated to have any operational issues. If they did, and if it could be linked to carbon build up on the valves, it can be easily remedied with an $11 can of CRC intake cleaner. False concern for a non issue that can easily be addressed. Thanks Valvoline. And ironically, Valvoline makes a good product. Too bad the marketing department thinks this is a good means to justify their salaries.
 
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529
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MA
Originally Posted by N Heat
Ive been learning alot from reading here lately about the DI engines and oil issues. How do you know if you have DI engine? My most modern vehicle is a 2012 4runner and Im assuming thats not DI.
The magic Google machine will tell you. Seriously, that should be one of the easiest things to find out about any vehicle. Not only is a 2012 4-Runner not DI...not even the 2020 4-Runner is DI. I have one DI engine (Honda Pilot) and one D-4S (RX350) engine. My guess is the RX350 engine will do significantly better over the long term as far as carbon. This is one more reason I may not keep the Pilot long term....
 
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33,503
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Southern NJ
Originally Posted by skyactiv
My wife had a Mazda3 with a Skyactiv engine, hence my user name. She bought it new. The Mazda got it's best fuel economy when new and didn't do as good when it had over 20k on it. I think deposits on the intake valves played a role. The car still for great gas mileage regardless.
That's odd. Mine stayed the same for almost 5 years/60k miles. I used M1 EP only which has a SA of .8.
 
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529
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MA
Originally Posted by buster
Originally Posted by skyactiv
My wife had a Mazda3 with a Skyactiv engine, hence my user name. She bought it new. The Mazda got it's best fuel economy when new and didn't do as good when it had over 20k on it. I think deposits on the intake valves played a role. The car still for great gas mileage regardless.
That's odd. Mine stayed the same for almost 5 years/60k miles. I used M1 EP only which has a SA of .8.
It's odd because one can't intuit carbon buildup based on lower fuel economy alone. Unless you look directly, you just don't know and that statement is meaningless.
 
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33,503
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Southern NJ
Originally Posted by PWMDMD
Originally Posted by buster
Originally Posted by skyactiv
My wife had a Mazda3 with a Skyactiv engine, hence my user name. She bought it new. The Mazda got it's best fuel economy when new and didn't do as good when it had over 20k on it. I think deposits on the intake valves played a role. The car still for great gas mileage regardless.
That's odd. Mine stayed the same for almost 5 years/60k miles. I used M1 EP only which has a SA of .8.
It's odd because one can't intuit carbon buildup based on lower fuel economy alone. Unless you look directly, you just don't know and that statement is meaningless.
That is true too.
 
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649
Location
Maryland
I have a BMW X5 3.0 si. I have the DI engine. What is the best way to keep the carbon buildup off the top of the valves? I am looking into the Seafoam treatment. Does anyone have any ideas on how to maintain this?
 
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Parts Unknown
over 100,000 miles on my current car, using high SA oil, and hasn't started to misfire, which is usually a symptom of excessive Intake Valve buildup. The only change from my previous car, religious use of additional fuel injector cleaner with every tank (1 oz of Renewable Lube fuel injector cleaner).
 
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649
Location
Maryland
Originally Posted by UG_Passat
over 100,000 miles on my current car, using high SA oil, and hasn't started to misfire, which is usually a symptom of excessive Intake Valve buildup. The only change from my previous car, religious use of additional fuel injector cleaner with every tank (1 oz of Renewable Lube fuel injector cleaner).
I have 142,4** on mine and she runs great so far. Will a good fuel injector cleaner help with this issue?
 
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