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Any issues with carbon deposits on intake valves?

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Vero Beach
#1
The Youtube post is 2 years old, but someone is mentioning about carbon deposits on the back of the intake valves 2 and 3 on ecoboost engines; or just all Direct Injection engines.

I've read a few posts here, but no conclusive answers, or any follow up on it becoming an issue.
If one regularly does highway, would you think the carbon will get shaken off, just like on the pistons?

Some videos recommend intake valve cleaning every 10k miles?

[video=youtube;SU8iUcPkq6s]https://www.youtube.com/watch?v=SU8iUcPkq6s[/video]

Thoughts?
 


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Atlanta
#2
+1 for answers.

I just watched Savagegeese's video on DI and it has me worried about maintenance. I haven't used any intake valve cleaner, and don't have an OCC either, so even though I have less than 25k on my '16 I'm sure it already has carbon buildup.
 


KKaWing

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#4
Ford doesn't recommend the spray stuff. They cite higher exhaust temperatures harming the turbo from the engine burning the chemicals. At this point, I think saving up a bit of cash for a good walnut blast would be the best bet. (Though they also don't recommend media blasting...)
 


TyphoonFiST

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#5
Ford doesn't recommend the spray stuff. They cite higher exhaust temperatures harming the turbo from the engine burning the chemicals. At this point, I think saving up a bit of cash for a good walnut blast would be the best bet. (Though they also don't recommend media blasting...)
They just want you to replace the cylinder head as a complete unit...Typical of Ford.
 


Quisp

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#7
There's a guy on ST Facebook group doing walnut blasting for 200 or 250 can't remember exactly. Had pictures of a 50k car , wasn't to bad.
 


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Location
Melbourne
#8
I searched it and found only Focus ST's walnut blasting their intake valves and reporting carbon build up ect but nothing on a Fiesta ST.. This could mean the Fiesta ST just dose not suffer from it as much. I am taking no chances though and now have an oil catch can installed.

I see here in this video that they recommend to NOT try cleaning the valves at all except using injector cleaners but it will still never reach the side of the valves that is needed anyway....

Video. https://youtu.be/-ynGWxzJHjA

Sent from my Mi MIX 2S using Tapatalk
 


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Location
Melbourne
#9
+1 for answers.

I just watched Savagegeese's video on DI and it has me worried about maintenance. I haven't used any intake valve cleaner, and don't have an OCC either, so even though I have less than 25k on my '16 I'm sure it already has carbon buildup.
I have done 67 thousand kilometres in my 2015 fiesta st and only just installed an oil catch can about 3 days ago.. it's 100% stock no mods and I bought it brand new and I have no power loss but I have run it on 98 octane from day one,. I use the most expensive oil and change it plus the filter every 5 - 6 thousand kilometres and it gets lots and lots of good hard driving.. never one single missfire either and runs perfectly. Just get a catch can and you should be fine..! [emoji4]

Sent from my Mi MIX 2S using Tapatalk
 


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Palmyra
#10
i had this issue on an Audi A3. It cost $800 including parts to fix... basically I took it to a auto specialist in town (CDI cars). they opened it up and used dental tools to scrape each value clean. it was mostly labor with a couple gaskets. Before I did this I took it to Audi, they tried SeaFoam.... when CDI looked at it they said the SeaFoam was useless because it just opened a path to the only valve that was still working well.

This was done on the Audi at 70K miles when it was driving like crap and misfiring. After the procedure it drove fine and lasted until I traded it in at 100K.

What I took from this ordeal is:

1) it can be fixed if you take it to a place that knows what they are doing
2) it ain't cheap
3) IMO the better the fuel the cleaner the burn and the less shat that makes it back into the intake.

So I will use 91/93 from a good gas station and hope I never have to do this.


Carl
 


JDG

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#11
CP-E quoted me $500 to walnut blast all the valves, they are down in Maryland. We definitely have some issues with carbon buildup but not as bad as the VW guys. My plan is to get them done around 75K miles (the same time I will probably have aux fuel installed to keep them clean thereafter).

The problem with carbon buildup is that the decrease in performance is so gradual that you never notice it. I don't doubt that it is there though and if you compared a stock car at 5,000 miles and a stock car at 75,000 miles you would see the decrease in flow volume and flow shape which would negatively affect horsepower. Whether than is 0.25HP or 10HP, I don't know.
 


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#12
I have had no problems and have run it on 98 from the day I bought it brand new 2nd month of 2015. Not a single misfire and no power loss that I can tell.. good oil and regular oil and filter changes help too and needs to be driven hard. 67 thousand kilometres on the clock now.

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KKaWing

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#13
Catch can just delays the inevitable though, the valves themselves (the stems) are lubricated by oil and no seal is 100 percent. Not saying don't use a catch can, but don't expect it to be *the* solution. It helps with one of the causes, but not all. Good oil, good gas, baffled catch can all help delay carbon build up... but in the end, soot from valve overlap will get on to the valves and the tiny bit of oil that makes it through the can and it little bit that makes it past the seal on the valve stem will catch the soot.
 


Capri to ST

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#14
There's a long (300+ posts) thread on this. I read it with interest because this is my first DI turbo car, and was feeling pretty good about this issue for our cars when I finished.For those who don't have time to read it, here's what I got from the thread and what I plan to do. Some of these things have been mentioned in this thread, and most are good things to do for any car:

-Use Top Tier premium gas
-Use high quality full-synthetic oil (which one is a whole other argument)
-Warm it up to full operating temp as often as possible, avoiding lots of short runs. If I have somewhere close to go to, I'll sometimes detour to a fun road nearby to warm it up and have some fun at the same time
-Give it an Italian tune-up sometimes, run it hard. It's a performance car, so enjoy it, and it's good for it from time to time
-Opinions on OCC's were mixed, with some feeling they'll be helpful, and some arguing that they won't, and that some of this functionality is already built into the car. I didn't get one

Some knowledgeable people also noted that Ford appears to have done a good job with engine and software design to lessen this issue, and that the more severe carbon intake buildup issues were present in some Audi, VW, and BMW models. Some Audis needed a cleaning every 10k miles or so. Ours may eventually, but I believe it'll be a good deal less frequent than on those cars.
Here's the big thread for those who are interested-
https://www.fiestastforum.com/forum/threads/3201-Ecoboost-Intake-Valve-Carbon-build-up
 


Last edited:

M-Sport fan

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#15
-Warm it up to full operating temp as often as possible, avoiding lots of short runs. If I have somewhere close to go to, I'll sometimes detour to a fun road nearby to warm it up and have some fun at the same time
EXCELLENT suggestion, and I do the bolded above on a daily basis to FULLY heat up the oil! ;) [twothumb]
 


OP
M
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Thread Starter #17
I've done some reading myself, and youtube watching.
"Engineering explained" happened to do a lot of videos on his channel about this, these past few weeks:

From his video, it appears like you're best off, running a Gasoline-Ethanol mixture, that runs cleaner than regular gasoline, or ethanol by itself:
[video=youtube;ATGSBi1kBl0]https://www.youtube.com/watch?v=ATGSBi1kBl0[/video]

I take the video with a grain of salt, since it's lab measured, but only for a 20 hour wear test.

Another video (forgot which) talks about a lot of oil in the valves, and carbon buildup, due to piston blow by.
This probably happens more often to those who are running on higher boost levels.

I don't expect any carbon issues on cars with 20k miles or less, even at higher boost. So I was hoping if someone had some real world experience with buildup (eg: checked the valves at a 25, 50, 75, and 100k miles interval).

For those interested in doing it themselves, this video shows at about 5:11 how to remove the intake manifold.
[video=youtube;yC6ahH_Ld1Y]https://www.youtube.com/watch?v=yC6ahH_Ld1Y[/video]

Once the intake manifold is removed (6 screws), one should be able to use an endoscope to peer inside.
Use a $4 Dental Pick Set, to scrape off any closed valves, and use a vacuum to suck out any carbon.

Shouldn't be too hard. However, I don't really like taking my car apart just to check.
In case someone has experience with this, it would be nice to know about how much crud to expect, at what interval.
 


TyphoonFiST

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#18
I've done some reading myself, and youtube watching.
"Engineering explained" happened to do a lot of videos on his channel about this, these past few weeks:

From his video, it appears like you're best off, running a Gasoline-Ethanol mixture, that runs cleaner than regular gasoline, or ethanol by itself:
[video=youtube;ATGSBi1kBl0]
]View: https://www.youtube.com/watch?v=ATGSBi1kBl0[/video]


I take the video with a grain of salt, since it's lab measured, but only for a 20 hour wear test.

Another video (forgot which) talks about a lot of oil in the valves, and carbon buildup, due to piston blow by.
This probably happens more often to those who are running on higher boost levels.

I don't expect any carbon issues on cars with 20k miles or less, even at higher boost. So I was hoping if someone had some real world experience with buildup (eg: checked the valves at a 25, 50, 75, and 100k miles interval).

For those interested in doing it themselves, this video shows at about 5:11 how to remove the intake manifold.
[video=youtube;yC6ahH_Ld1Y]
]View: https://www.youtube.com/watch?v=yC6ahH_Ld1Y[/video]


Once the intake manifold is removed (6 screws), one should be able to use an endoscope to peer inside.
Use a $4 Dental Pick Set, to scrape off any closed valves, and use a vacuum to suck out any carbon.

Shouldn't be too hard. However, I don't really like taking my car apart just to check.
In case someone has experience with this, it would be nice to know about how much crud to expect, at what interval.
Get a HD Borescope from Amazon...they are like $20-30 dollars and use and app with your phone and plug right into any phone. Its the same type of tool they use in the doctors office for endoscopy's to look down into your throat or lungs.[like]
 


Last edited:
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#19
Get a HD Borescope from Amazon...they are like $20-30 dollars and use and app with your phone and plug right into any phone. Its the same type of tool they use in the doctors office for endoscopies to look down into your throat or lungs.[like]
Still have to take intake manifold off tho don't you??

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