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Watch A Tech Tackle Ford EcoBoost Carbon Deposits: Video

Direct injection, as used on FoMoCo’s line of turbocharged EcoBoost engines, has generally been a welcome advancement for the gasoline internal combustion engine, with increased levels of power and efficiency. However, there are inherent drawbacks from a carbon-buildup standpoint, because of where the fuel enters the cylinder head. In the video below, a technician manually cleans the intake valve deposits on a Ford Focus with 87k miles.

The video doesn’t show the process of removing the intake manifold, but that would be a prerequisite for this sort of work. With those components out of the way, we can see a row of intake ports leading down into the cylinder head. The technician explains it is extremely important to ensure the cylinder being worked on has the intake valve completely closed. The engine will also need to be turned over manually using the crank pulley, in order to accomplish this for each cylinder. The objective is to remove all the layers of gunk without dropping any into the combustion chamber of the cylinder below.

Starting with a completely closed intake valve, we can see the technician explain and follow a multi-step process to persuade the carbon out. Initially, he uses compressed air to blast away any loose particles, then scrapes the deposits carefully with a pick and wire brush to loosen them, checking with a flashlight to gauge progress along the way. Once the large chunks are removed, he cleans the same intake runner and valve again, alternating with a wire brush and solvent multiple times, and using compressed air to blow out the resulting debris.

After a few minutes of work, the tech ends up with a much cleaner intake runner and valve surface. The process must then be repeated for each cylinder, turning the engine over, if necessary, to completely close the intake valve on each one.

Unfortunately, early EcoBoost motors with direct injection will likely have these carbon deposits, and generally require a periodic cleaning to preserve the engine’s drivability. This is one reason why The Blue Oval has chosen to incorporate both port and direct injection on the latest generation of EcoBoost motors, as well as the latest Gen 3 Coyote engine.

Previously in widespread use by itself for decades, port injection sprays fuel through the intake runners and sends it right by the intake valves, helping to keep them clean. A dual injection setup, one that contains both port and direct injection, is now becoming more common. It delivers added advantages in terms of performance and efficiency, thereby providing the best of both worlds.

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  1. Joe fuss

    So, if I read this read this right, the newer gen Ecoboost engines, with port and direct injection, are not likely at risk for carbon buildup…?

    I have had three 2.0 Ecoboost, earlier generation, Escapes, with only Direct injection, two up to 70,000 and 80,000 miles.. with no drivability issues, or any issues at all…
    Though I do drive my vehicles in a spirited fashion.. (flooring it from time to time, on a regular basis)… Does driving like yer grandma, contribute to the carbon buildup issue ?
    I wonder…..?

    1. Justin LaNoue

      No, driving in a spirited manner doesn’t cause the valves to get anywhere close to the temperature needed to burn anything off of them on the intake side. Easiest thing to do is to manually clean them every 50k-100k. I have a video up on YouTube of my old Focus ST valves and their condition and that was with multiple track days and redline pulls everyday. The 2.0 and 2.3 are solid engines though even with the buildup, don’t stress out about it.

    2. Michael Cook

      Joe I have a 2.0 Ecoboost Escape, our vehicles have this issue. The engine pulls oily fumes from the block and the gunk bakes to the valves. Ive installed a oil catch can and sprayed some seafoam on top of the valves. Helped a bunch, the pcv valve system is setup stupid. It needs to be cleaned on the regular to be honest.

  2. Glenn c Kayea

    So do the 2019 Ecoboost 2.0 and 2.3 have port and direct injection ? Escape and Ranger respectively.

    1. Justin L.

      No they do not. Only DI.

  3. Phill W

    They should tell people in the Owner’s Manual, “From time to time, give your EcoBoost the old ‘Italian Tune Up.’ “

  4. Neil

    Ford has fixed these issues on all new EcoBoost engines. I drive an F150 with a 3.5 liter EcoBoost and 10 speed transmission. This truck has an immense amount of power, tow capability and excellent fuel economy. I love my Ford and I’m thankful that they developed this type of double turbocharged engines in their full size trucks. My truck has a big fuel tank at 136 liters but I love how I can drive 11-1200 kms on a full tank.

  5. ThrottleJockey

    As a reply to Neil. Driving dynamics don’t play that much into the carbon deposit issue on a DI engine. The problem is EGR and a closed PCV system (no catch can). If you could delete the EGR system (and still meet emissions) and install a PCV catch can you’d essentially eliminate the carbon issue. It would certainly help to increase the engine lifespan.

  6. Jeff

    Why not put a catch can on the car tap into the PCVsystem with a catch can to condense what gets past the rings into the crankcase into the catch can therefore protecting it from coking up the back of the intake valve? Having two injectors per cylinder to me seems overly complicated.

    1. ThrottleJockey

      You’d still have carbon buildup from the EGR system.

  7. Michael L McCollum

    @joe fuss, correct! That is why ford and others(toyota) went to port/direct injection. The port injection will clean the runners and valves like the days of old…..

  8. Michael L McCollum

    @jeff, I agree but you know if the manufacturer does it, they will charge 3x what the part costs.
    Lots of companies make them specific for the 3.5l ecoboost for the F150. Even recommended by lot of tuners for the first thing to do

  9. Itsa memario

    The carbon build up comes from the PCV system, which draws in oil vapors from the crank case and burns them, some builds up on the valve and polymerizes similar to seasoning a cast iron pan. The EGR system which recycles exhaust gas in to the intake to lower combustion temperature also contributes to the build up since direct injection produces more soot (same injection process as diesel engines). Adding an catch can to the PCV system will help, unfortunately there isn’t much that can be done for the EGR system while keeping the vehicle emissions compliant, a particulate filter would help but maintenance on them is generally terrible.

  10. Eric Bolden

    I have a 2010 Taurus SHO that i drive has 228,000 with no engine issues EVER…But sadly now the tranny is showing its age…i plan on keeping this car for a long time ( love the size and performance) looking to rebuild or replace motor and trans in the near future

  11. Old mechanic turned engineer

    The problem is using Ford’s synthetic blend that out gasses VOCs that need to be dumped back into the intake. If want turbos and GDI use real synthetic oil. Look at the specs for each oil. It’s obvious cheap oil out gases and forms carbon upon exposure to hot valves.

  12. Lee

    AMSOIL full synthetic y’all. Cures nearly every oil related issue, and there’s nothing better.

  13. Mark L Bedel

    I had this exact service done at 25,000 miles on my Focus ST. After the cleaning I had a Catch Can installed which is supposed to capture most of the PCV extracts so they don’t end up on these valves. Currently i have about 42,000 miles on the car but haven’t checked the valves to see how well the catch can is doing it’s job.

    I can tell you that since the initial cleaning, I’ve almost filled a large Mason Jar with the catch can discards. It’s interesting how after watching the discards settle out, there seems to be three layers, presumably water being the heaviest at the bottom, condensation due to firing a cold engine? Then oil then I presume gas, all neatly striated in the jar. So, it just not the oil that is at issue here.


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