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High Mileage Owners Chime in regarding intake valve deposits.

Capri to ST

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#41
I'd be very surprised if it's carbon at that low mileage. It appears newer GDI cars like ours are less prone to it, and Ford has done a good job to minimize it. One member has reported over 174k miles with no carbon buildup related issues.
 


M-Sport fan

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#43
I do not have a catch can. I'm kinda worried because I have no other idea of what the issue could be.
I know it is REALLY early on, but did you check the plugs??

I've heard of them being fouled enough to get symptoms like yours, but not enough to throw misfire CELs/DTCs. ;)
 


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#44
I know it is REALLY early on, but did you check the plugs??

I've heard of them being fouled enough to get symptoms like yours, but not enough to throw misfire CELs/DTCs. ;)
CORRECTION: I DO have a catch can, but I only put it on about 1k miles ago. Too little too late. I was blown away by the amount of oil it collected in such a short period of time. I'd say about 2-3 teaspoons.

I haven't checked the plugs. I'm also thinking about reverting the ECU back to the stock tune to see if that's the root of the problem.



 


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Sinking Spring
#45
I have 3 ecoboosts. I have read a ton about this subject. My opinion is that this will not be an issue for the vast majority of ecoboost owners. Catchcans I feel are not the end all answer. Due to valve overlap, there is combustion products from the combustion chamber blown back on the intake valves. This is not cleaned by fuel on our engines. My opinion is to run great fuel (top tier), great synthetic oil every 6 months or 5000 miles, and Techron at each oil change. These things will run strong and smooth if you keep the combustion system as clean as possible. Car and driver ran a focus st for over 40,000 miles with no performance change....

"A consistent runner, the ST returned identical 60-mph and quarter-mile times, and even the same 96-mph trap speed, with 40,000 miles on the clock. True, the 5?60 mph, 30?50, 50?70, and all the acceleration times above 100 mph improved, indicating that a few horsepower were unleashed over its 13-month stay."

Here is a video of a f150 ecoboost with over 200k on the odometer...

https://youtu.be/b_CXoPdTBUE

Do your maintenance and drive.
 


Zormecteon

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#47
and Techron at each oil change. .
I run strictly Chevron.. well, one tank in 50 I'll put in Shell, but only if desperate for fuel and there aren't any Chevron stations available)....

Still think I need the Techron once every oil change? ..

As an aside, I had a 1988 Tempo Sport. I ran it over 100,000 miles on ARCO but noticed a performance degradation about that time, so had it's first tune up (I bought it new) done. It still wasn't quite right, so I bought a bottle of Techron and ran it thru. I noticed an immediate improvement. I'm not generally and additives adder or believer, but this stuff works.
 


M-Sport fan

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#48
^^^As do the other high PEA content fuel additives (Red Line SI-1, Amsoil Pi, Gumout Regane Fuel System Cleaner). [wink]
 


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#49
Agreed. I know the OCC is only a stop-gap measure. Too little, too late in my case it would seem. I've always used Chevron fuel and fully synthetic oil changed at 5k mile intervals. The I it difference is I do run a Mountune time on it. Maybe it accelerated the accumulation of carbon. Checked the plugs and all were good except cyl one which had some carbon buildup but not sufficient to cause a misfire. Still not CEL With all this rough idling.
 


Intuit

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#50
"Check Engine Light" is really just a "Check Emissions Light". Short of a stall, they never really activate unless there's a problem that generates "excessive" emissions. Fortunately they don't activate with emissions problems that exist at the accelerator pedal.
 


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#51
"Check Engine Light" is really just a "Check Emissions Light". Short of a stall, they never really activate unless there's a problem that generates "excessive" emissions. Fortunately they don't activate with emissions problems that exist at the accelerator pedal.
True. I had a friend hook-up his Snap-On diagnostic computer and he said the vehicle was logging several misfires. He didn't tell me which cylinder(s); stupid me I should have asked. No active or pending codes to speak of as well. I uploaded a YouTube video of the misfire. It comes through the audio as intermittent "pops." It's better to listen to the video with headphones if possible.

https://youtu.be/IUFX5wS8eAk
 


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#52
Embarrassed to admit it, but it was a bad batch of fuel. Refilled the tank the other day and its running smooth again. It was a local Chevron station near my home. I think they mixed the octanes because my receipt reads Premium.
 


dhminer

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#56
Month after purchase. I did a CRC intake cleaning 10k ago , don't know how much that contributed .
Awesome thanks for the update. Never used the stuff but Iā€™m going to peep my valves at 75k and see how they look. Ran with no OCC for 70k miles and havenā€™t cleaned shit.
 


Old Mike Emerson

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#59
I just watched Legitstreetcars video on cleaning the carbon on a Mercedes v-12 with over a 100k miles. It was ugly to say the least, not only did the valves have loads of carbon, but the intake runners were nasty with baked on oil from the PVC and EGR systems. From working on the 2.5 24 valve Duratec Contour and the 4.6 Mod motor I can say from personnel experience that a catch can makes a difference.
 


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