Pulled intake and found carboned up valves.

[Fordiesel69]

My 3.3l ford has documented 222 idle hrs and 30xx total crankshaft run hours with 142k. Based on service records and condition there is zero question it was a highway beast. Now that I peeled off the intake manifold to do plugs I noticed that the valves are clean only one their seats but the stem and fillet area are heavy on carbon. For this being a GDI / PFI dual I was kinda bummed to find this. There are no symptoms or issues so I am hesitant to go any further.

1. How can I make the engine favor port injection for a while to use and additive?

2. If I use the zip tie method and let's say some carbor breaks loose can this ruin the intake valves from it not sealing?

 

[supton]

Pics or it didn't happen.

Err, what I mean is, what looks bad to you might not be what others think look bad. Can you post just how bad it looks?

Given how some engines can inhale a good portion of the plug and yet carry on, I have to think some slimey carbon that gets knocked off and inhaled is unlikely to do much if any damage (at workse, smooshed down and then out the exhaust). But not quite the risk I'd want to take either!

 

[meep]

There’s a white paper out there on this, at least for ford’s dual mode ecoboost motor. The port injection is surprisingly used a lot more than you’d think. If memory serves, it’s primarily used under low throttle conditions, then DI phases in, and and then the port injection eases back in under heavy throttle. maybe. But the point is, the port injection gets used a lot, especially in normal driving.

 

[MVAR]

Did a walnut shell cleaning on my wife's '13 Fusion 2.0EB at just over 100k miles. It was running rich & would puff out black soot whenever accelerating hard. When removing the intake, there really wasn't much buildup (in comparison to my old Mazdaspeed6 or friends BMW). Some engines seem to be more sensitive than others. My old Speed6 still ran decent even with what looked like a massive amount of buildup. This Fusion had probably 10-20% as much but lost a few mpg & responsiveness in the process.

Fusion now has 181k miles on it & I'm planning on another walnut shell cleaning around 190k as it's just starting to puff soot again when following her on a hwy onramp.

If you're not noticing any issues from the buildup, maybe take advantage of a high detergent gasoline like Chevron or Shell V Power and let the port injection do some cleaning for you?

 

[i6pwr]

BG44K Platinum is my goto once a year on each vehicle I have. Best stuff to clean carbon deposits IMO.

 

[KGMtech]

BG44K Platinum is my goto once a year on each vehicle I have. Best stuff to clean carbon deposits IMO.

Not effective for cleaning intake valves on GDI engines.

 

[Cujet]

As a general rule, dislodged carbon bits won't hurt the combustion chamber, pistons or valves.

You could try Berrymans B12 spray, as that is one of the products that will, to some extent, dissolve carbon. Another option is oven cleaner.