Hi All, my first time posting here....very nice forums! I have a 2011 F150 XLT with the 3.5 EB. I have noticed the tailpipe is covered with black soot for some time now. The other day I went to pass a slow moving car, dropped the accelerator to about 3/4 throttle. The truck kicked into passing gear and the engine began to rattle similiar to being out of time or too much fuel. Passed the car and look back and a HUGE cloud of black smoke. No warning light came on and the truck seemed to run fine. Went a few miles further and passed another car.....same thing. Now I am concerned. At the base of a long steep hill I slowed done to about 40 and punched it, watching in the passenger side mirror only a small puff of smoke this time. Did this several more time and no more smoke. Called the dealer and got the run around....saying I needed to blow out the carbon. My thoughts is this isnt a 70' vintage carburated vehicle. The fuel meter is computer controlled and this shoudnt be happenning. I guess I will try some injector cleaner and see if that hepls. Any one else heard of this problem. Thanks

 

My tailpipe is pure black also, and so thick you can flake it off. Can't say I've noticed it smoking though. I definately "blow out the carbon"... Let us know what you figure out.

 

I don't own an EB but your right a computer controlled vehicle should not do that. At least the many I have owned never have. There has to be an issue of a rich condition. Why no CEL there is the mystery in my opinion.
Craig

 

crappy fuel we use. my 2 cents..

 

To the OP, I think it would be important to know the weather conditions that day. We all have the heavily sooted tail pipes but mine has never blown or puffed any smoke that I know of. I drop the hammer every time I enter the freeway if possible.

 

Thin start up creates most of the carbon on the tailpipe. Select tow/haul for a more agressive shifting pattern to help clear it out.

 

Thanks for the responses. As for the weather that day, it was clear with low humidity and around 65 degrees. I have been driving the truck harder than before and have not had this problem since. Regarding the fuel....that poses an interesting question. We all know that ethanol is problem and can kill milage. I work in a refinery and know first hand the damage ethanol does. Nearby there is another refinery and they are blending liquid Butane into there gasoline. It is a byproduct and this is the easiest way to get rid of it. So, when I buy fuel it is a 50/50 chance that it came from the refinery that blends butane. I can tell by the odor who made the gas. Just some food for thought on fuel and performance.

 

The TSB is 12-10-19 and replaces the CAC's in those trucks already built.
It also looks like the new trucks are coming in with yet a third version of CAC with different connections and ports (which couldn't be retro fitted to existing trucks)<!-- google_ad_section_end --> <!-- / message -->
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My truck also puts out a big black puff at WOT. Dealer told me it's normal. Truck runs fine with no misses, and accelerates strong and smooth. Not sure what to think.

 

The Ecoboost is direct injected and direct injected gasoline engines sometimes have issues with coking. They build up a lot of carbon around the injectors and valves, which sometimes breaks loose and burns off.

Audi has had problems with this for years:

Audi FSI Engine Carbon Build-up Megathread

In some engines it can get bad enough to cause problems, but as long as the truck is running fine now I wouldn't really worry about it.

 

Have heard of ethanol helping with the carbon removal.

 

I have the same problem with mine. Allot of black soot on the tail pipe but no performance problems.