I was wondering if duel injection solved the intake carbon build-up issue, here's an answer..
Video: How much does duel injection help carbon build-up
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Thanks for the post. So is the added cost of dual injection worth it, or should they just go back to port injection. The venerable 6.0 Chevy in the 3/4 tons has been replaced by the 6.6 with direct injection but no dual injection AFAIK.
Properly executed PCV solves issues. BMW had CBU issues in N54 (2006-2010) and after that they didn’t have issues anymore.
Toyota 2GR-FKS has dual injection and no CBU issues. Their 2.5 V6 has abysmal CBU issues and no dual injection. That tells me that Toyota had to go more complex solution bcs. they couldn’t resolve it with PCV only.
I think direct injection is here to stay because of its' advantages over port injection. Unfortunately, looks like occasional walnut shell cleaning of intake valves is here to stay as well.
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dnewton3
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dnewton3
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Duel injection, IMO, does not stop the carbon build-up problem. What it does is retard the rate of build-up. It's not so much a question of "if", but "when" it will become a problem big enough to warrant addressing.
This video is clear evidence that in this particular application (3.5L EB), it does indeed help reduce the rate of build-up. It's obvious that the valves are in better shape with the dual injection system than DI only. It's also readily apparent that the problem still exists, and rather than having to blast the valves clean at 125k miles, it may be perhaps 200k miles before codes start setting and driveability issues arise. Hence, my comment about rate of contamination.
Other brands (or even other engine designs within the Ford brand) may have different results. This is anecdotal evidence; a sample size of 1 (one) isn't exactly science. But it is at least a data point to give some meaning of reference.
It would also be interesting to know if the new dual-injection systems would see added benefit from a catch-can. Perhaps, between the dual-injection AND a catch-can, the rate would be slow enough that 250k or more miles could be done before a major issue arose? I think to many folks, if that kind of rate were common, most folks would accept it (not like it, but accept it) as not too intrusive in the ownership plan.
This video is clear evidence that in this particular application (3.5L EB), it does indeed help reduce the rate of build-up. It's obvious that the valves are in better shape with the dual injection system than DI only. It's also readily apparent that the problem still exists, and rather than having to blast the valves clean at 125k miles, it may be perhaps 200k miles before codes start setting and driveability issues arise. Hence, my comment about rate of contamination.
Other brands (or even other engine designs within the Ford brand) may have different results. This is anecdotal evidence; a sample size of 1 (one) isn't exactly science. But it is at least a data point to give some meaning of reference.
It would also be interesting to know if the new dual-injection systems would see added benefit from a catch-can. Perhaps, between the dual-injection AND a catch-can, the rate would be slow enough that 250k or more miles could be done before a major issue arose? I think to many folks, if that kind of rate were common, most folks would accept it (not like it, but accept it) as not too intrusive in the ownership plan.
DI still looks a problem still in search of a solution. JMO
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It’s definitely cleaner than the DI only he showed. But I’m more concerned on why a 2019 Ford F-150 with 125k miles already needs a complete timing job? 
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Dual ?
I had the same thought. Wonder if shorter OCI's would have helped?It’s definitely cleaner than the DI only he showed. But I’m more concerned on why a 2019 Ford F-150 with 125k miles already needs a complete timing job?
Much more expensive than the intake carbon issue the video was addressing.
It will be interesting to see if OEM's will be able to engineer DI and PCV systems so that carbon build up a non-issue someday. I have a catch can on my Impala, and I don't mind emptying it occasionally. Not sure if the catch can will make much of a difference in the long run. I would love to see a comparison of two identical fleet vehicles (e.g. taxi's), one with and one without the can to see the difference after 150,000 miles.
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DON'T own any DI + would never buy one along with CVT trannies!!! i guess carbon issues vary with various vehicle models as its a crap shoot for sure like all the other new tech!! sure theres a bit better mpgs + performance BUT you will PAY for it if you cant afford to trade often $$$$
As long as the oil meets OEM spec I don't think it would make much if any difference.
You would like to think a good oil, as well as keeping up on regular oil changes could help. It's what ever can vaporize and/or aerosol out of the oil and combustion process that is causing the build-up in the first place.
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My BIL got rid of his ecoboost after 2 turbos and then more issues all before 130k miles. He was told they start getting expensive or often need replacement around 120-140k miles. People probably ignore the timing chain noise and blow up the motor. 200k without major repairs is a roll of the dice these days and not the norm like the 2v mod motors.It’s definitely cleaner than the DI only he showed. But I’m more concerned on why a 2019 Ford F-150 with 125k miles already needs a complete timing job?
According to the video, it should last around 250K before walnut cleaning is needed. Not a lot of people are going to keep their car that long.
Also, someone in the video comments mentioned despite having a dual system, they used cleaning chemicals every 50K. I think that is the way to go.
D4-S has been around since at least 2005, on the 2GR-FSE on the IS350 and other Lexus.
The simulated Atkinson cycle also has the added benefit of additional fuel washing of the valves, from the delayed closing of the intake valves which the fuel-air mixture is pushed back through the intake valves to reduce pumping losses, at the expense of of low end power/torque.
and the 2GR-FKS has a injector self cleaning mode, that works during idle.
Audi claims they went with Dual Injection to meet more stringent EU emissions standards
I know they have it since 2005. They also had IS250 since then which is biggest offender of all when it comes to CBU.
BMW since N54 doesn’t have those issues nor it is necessary to go dual injection. N55 while nit having Atkinson cycle, don’t have CBU issues nor N20.
B46/48 and 58 do have Atkinson cycle, but I would say for different reason.