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Has anyone experienced intake valve deposits?

XR650R

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#1
We've all seen and heard about DI engines getting massive carbon deposits on the intake valves. Has anyone experienced this with their Fiesta STs?

I'm aware that some of you have put a lot of miles on the little beast. Just curious.
 


kivnul

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#2
[MENTION=929]antarctica24[/MENTION] has some of the most miles of any car on here, dunno if he has had a look at his valves.
 


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#3
I have 84,000 miles on mine. I haven't looked at them once. I probably should, but i have to find time to rip off the manifold. Now that I have a "back-up vehicle" It might be a good idea to take a look and find someone to clean them sometime soon. I haven't noticed any decrease in MPG or performance so, this is not tops on my list.
 


Capri to ST

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#4
There's a long thread on it-
http://www.fiestastforum.com/forum/threads/3201-Ecoboost-Intake-Valve-Carbon-build-up

I don't recall anyone reporting a problem with it. The thread noted Ford had done a good job with software to mitigate potential problems. It also appears the cars having the most problems with this are ones with earlier generation DI engines, like Audis and VWs.
From reading about this issue, the things I plan to do to prevent or lessen it are-
1- Use Top Tier gas
2- Use a high quality full synthetic oil, preferably with a low NOACK (volatility) score
3- Warm it up to operating temperature as often as possible, avoiding lots of short trips
4- Give the car an Italian Tuneup from time-to-time (which is fun anyway, right?)
5- Some are using catch cans. I found mixed opinions on their usefulness
 


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#5
Glad you said something I've been been concerned recently too. Mines approaching 60k, on the stock tune, and almost two winter seasons. It would be nice to stick an endoscope / inspection camera in there to document the buildup. My problem is I don't have one. If anyone is willing enough to lend out one of theirs, maybe we could all learn something. Just a suggestion but also really interested in the results. [popcorn]
 


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XR650R

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Thread Starter #8
This guy cleaned up a 2.0 Ecoboost in an Escape, using a screwdriver. I'm guessing it didn't get enough Italian tuneups. A VW mechanic talking about it on another video said it was less of an issue with GTi's than with more sedate VWs, probably because they were driven harder.

https://www.youtube.com/watch?v=DgNipNVHq8o
 


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#9
i think [MENTION=2728]CP-E Mitch[/MENTION] can anwser this
When I have over 50K miles on mine, I am heading there (CP-E) to give my valves the toasty walnut shell blasting treat. [wink]

Until then, I am doing EVERYTHING on Capri to ST's list above (including the catch can/air-oil separator), plus, I plan to use a FULL synthetic (group 4/5, PAO/POE base stock) oil on the next OCI which specifically is engineered to lessen the possibility of these deposits with BOTH an ultra-low volatility rate AND a detergent/dispersant additive pack composition which inhibits deposit formation when burned in the combustion chambers.
 


A7xogg

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#10
We're not even close to vw level cause all these guys with 50k miles would be complaining how there car can't drive when it's cold out because it's misfiring that bad
 


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Thread Starter #11
After reading this and all the links provided here, I'm not worried. It seems the FiST doesn't have this problem, due to design, and possibly, because it's hard to resist stepping on it now and then. Looks like Capri to ST summarized it well.

I've yet to see an ST owner post anywhere about having this issue, and there are some with lots of miles on them. antarctica24 had 181,000 miles last I saw, and he put a faster turbo on it, among other things. No mention of any problem with the valves.

This is all anecdotal, but we know what to do: Top tier gas, oil made for GDI engines, (like this stuff, or something similar: https://team.valvoline.com/promo/modern-engine), avoiding short trips that don't really warm it all the way up, and enjoying that power you paid extra for once in a while.

I like the idea that winding it out now and then is good for it! "But officer, I was just taking good care of my car!"

If it ain't broke, don't fix it.
 


Capri to ST

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#13
Someone wondered whether antactica24, probably the owner with the most miles on his car at ~185k, had had this problem. Hopefully he'll chime in, but he used to live near me and I asked him about this. He said his gas mileage had stayed very consistent up to 150k or so when he tuned it, indicating to him that he didn't have carbon buildup. I don't know if he checked it directly.
 


haste

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#14
My fuel mileage has gone to crap recently...wonder if I should get mine cleaned. I'm at 60k miles and have had an X-37 on the car for over 25k now. It's been tracked for two full weekends and one autocross, I don't baby it often. I do not have an OCC installed.
 


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i think [MENTION=2728]CP-E Mitch[/MENTION] can anwser this
I saw this mention pass through my inbox a while ago and meant to follow up.

Im about to touch 40k miles which means its time to take a look at the valves again. Ive made alot of changes to the car since I looked and cleaned at 20k, so, the engineer in me is going to say whatever results I have are inconclusive, but itll still be interesting to see if/what difference running a catch can may have made.

One thing to note, on alot of the GDI cars I have blasted, it seems that intake manifold flow does seem to have a small effect on which valves are worst. The center on the focus ST and 335i are usually the worst. The heavier oil has less of an ability to change directions so it goes to the cylinders that are straight on. 1 and 6 on the 335i's are usually a little cleaner.

The carbon buildup is so gradual too. If your loosing any power from it, it most likely isnt a high enough rate to measure and account for the ring wear and other factors.

Still yet to do a before and after dyno of JUST walnut blasting on a bad car.

One thing I have seen is that the buildup can effect the sealing of the intake valve. If the carbon sneaks onto the edges of the valve (usually most of the buildup is concentrated around the stem), it can hurt valve sealing. I am yet to pressure test a cylinder head on a MZR or Ecoboost that has had a perfect valve seal when removed from the car. This is also exacerbated by not having the cooling effect of the fuel on the valve.

I dont see driving it harder helping much if at all. The theory seemed to revolve around more fuel past the valves and everything.
 


M-Sport fan

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#16
^^^Mitch;

In your opinion, is the volatility of/ability of the oil to be vaporized pretty much the main factor/contributor to this carbon buildup (thereby justifying the use of the LOWEST volatility rated oil possible), or is it mostly the DI setup itself responsible, and would still occur even with a ZERO volatility rate oil (IF that were possible, which it is not)? [???:)]

Even though yes, they are TOTALLY separate problems, the same question applies to the prevention of LSPI, given that one is already using a top name brand, top tier fuel (like Shell V-Power 93 or such).
 


Intuit

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#17
I'm on the street. I don't baby it once the engine is warmed. I'm not racing it. As long as there aren't any idle or running issues, I don't give flying turd.

People can be overly anal about how clean their intake is. The throttle plate on my prior vehicle had engraved print on it stating that it had a special non-stick coating on it and specifically warned/instructed people not to clean it because that will damage that coating. People cleaned it anyway, even though it didn't need it, never mind that there weren't any resultant performance or safety issues. Then some would claim that it was getting dirty.

This was the intake from my prior vehicle at ~190k miles.
https://1drv.ms/i/s!ABsZJDCN8kMMgRg
This is from PCV + EGR. That stuff was wet, loose and could be carb-sprayed and wiped out with a rag. Didn't make one lick of difference regarding engine performance. The (pre-EGR, pre-PCV) throttle plate of course was perfectly clean.

Didn't matter that it wasn't GDI, people still ran oil catch cans on the PCV.
This must've been to prevent cylinder head build-up right?
So what did cylinders 1 and 4 look like? (ignore 2 + 3 due to coolant leaking into cylinder)
https://1drv.ms/i/s!ABsZJDCN8kMMgTY
https://1drv.ms/i/s!ABsZJDCN8kMMgUE

Don't have the fuel with GDI but air velocity is going to be much higher at the valve versus intake and we don't have EGR that I'm aware of. No EGR and higher air velocities at the valves should lend an advantage.
 


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#18
^^^I ran a catch can (Moroso) on my port injected (and YES EGR equipped, which most in non-emissions states promptly/totally removed and 'wrote out' the resultant DTC/light) LS1 only because the LSx intakes always seemed to get excessive oil spray, and carbon soot residue in them, and I did not want there to even be a chance of that getting into the combustion chambers and reducing the octane of the mixture at all (MUCH less about valve cleanliness than in a GDI setup). ;)
 


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#19
^^^Mitch;

In your opinion, is the volatility of/ability of the oil to be vaporized pretty much the main factor/contributor to this carbon buildup (thereby justifying the use of the LOWEST volatility rated oil possible), or is it mostly the DI setup itself responsible, and would still occur even with a ZERO volatility rate oil (IF that were possible, which it is not)? [???:)]

Even though yes, they are TOTALLY separate problems, the same question applies to the prevention of LSPI, given that one is already using a top name brand, top tier fuel (like Shell V-Power 93 or such).
I think you bring up a valid point. The last walnut blast I did on a focus ST, the owner had been using amsoil for most, if not all of the engines life and the valves were a little cleaner than I would expect at his mileage. I believe amsoil is known for having lower volatility. They were still dirty, but less so.

I think overall, between using better oil AND filtering crankcase gasses, you will have less buildup, but without fuel past the valve, there will always be buildup. Even so, cars I have run with AUX weren't perfect, but it was more of a layer of grime vs actual carbon deposits.

Our cars dont have EGR due to dual variable valve timing (or VCT as ford calls it) which gives the ability to add valve overlap. Wierd enough, there is no additional overlap at startup. Only really happens in cruising to add fuel economy.

Here is said focus ST customer (60-70k i believe and PCV catch can installed)

IMG_0416 by mitchlevy7, on Flickr

after

IMG_0418 by mitchlevy7, on Flickr

You can see that its actual effect on the airflow past the valve is pretty minimal.

Once you get to this point (BMW n54, forget mileage)

IMG_0784 by mitchlevy7, on Flickr

You can see that the buildup is starting to get in the way of airflow. The n54 actually has a heating element in the PCV system as it goes from the vent back into the intake to help atomization (more likely so that the compressor housing doesnt fill up with liquid oil)

Ive also tried using solvents during the process. It helps loosen the big chunks a tiny bit and cleans the port itself, but it doesnt really get anything off the valve. The results are the same just using walnut media.
 


M-Sport fan

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#20
^^^Isn't it that said overlap in our EcoBoost VCT systems which allows the dirty combustion gases to gunk up our intake valves in the first place (in addition to 'baking' the vaporized/volatilized oil spray onto them)? [dunno]
 




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