Deposts on DI engine valves

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Originally Posted By: novadude
As bad as those ecoboost valves in the picture above look, I have pulled apart MANY 60s-70's era small block Chevy engines that looked just as bad if not worse.

Sure, they might have been down on power, but not by any amount that was extremely obvious to the daily-commute driver. No apparent drivability issues with gunked up valves - they all started fine, idled fine, ran OK at part throttle around town, etc.

I'm not saying that these deposits are a good thing, but the people that shriek in horror at photos like the one shown above should remember that we've been living with IV deposits for many, many years.



thumbsup2.gif
 
Originally Posted By: novadude
Originally Posted By: Olas

The options are to install a wet manifold or divert PCV and EGR away from the inlet.



That won't fix it either. Valve seals are designed to have a "controlled" leak. If you didn't allow oil past the valve stem seals, valve stems would be running dry, which would male for a pretty short life.

Eliminate PCV or install 3 catch cans in series, and you are still going to have oil getting on your valves. I personally feel that expensive catch cans are $300 snake oil. Sure, you can see what they collect, but how much of that fine oil mist would have stayed in suspension in the high vacuum intake manifold environment and sailed on past the intake valves?


Sure, valve stem seals allow a very small quantity of oil to pass them, but in a well maintained engine and in a thread about DI IVDs, stem seal leakage is not really relevant.
Nowhere did I mention catch cans - I like to vent to exhaust. As far as the percentages of how much stays suspended in the charge and how much gets deposited on the valve is also a side argument - vent to exhaust and none of it settles inside your engine.
 
How do we know the picture of the valve deposits are really from an Ecoboost engine. Just askin.
 
Originally Posted By: Carguy21
Well, Toyota is known for reliability, so now they are comming out with DI engines in many models, including some known for reliability like the Tacoma and RX350 - IMHO they took the carbon formation on the 2GR-FKS very seriously. Do any of you know what the did on that engine to prevent it if the did something?

These engines combines regular multipoint injection with DI. When strong acceleration is required, DI is used whereas relaxing cruising on highway activates MPI. So the buildup during DI is removed as before.
 
Originally Posted By: Carguy21
I if there is something the owner can do.


Drive it!
 
Originally Posted By: demarpaint
Originally Posted By: KevinP
I'm sure the DI issue will eventually get resolved. In the meantime, I'm happy to not have one.


That's exactly how I feel.


Dermapaint. Would that can dripping help in this gdi regard?
 
Originally Posted By: novadude
Originally Posted By: Olas

The options are to install a wet manifold or divert PCV and EGR away from the inlet.



That won't fix it either. Valve seals are designed to have a "controlled" leak. If you didn't allow oil past the valve stem seals, valve stems would be running dry, which would male for a pretty short life.

Eliminate PCV or install 3 catch cans in series, and you are still going to have oil getting on your valves. I personally feel that expensive catch cans are $300 snake oil. Sure, you can see what they collect, but how much of that fine oil mist would have stayed in suspension in the high vacuum intake manifold environment and sailed on past the intake valves?


Guess it depends on the engine and how much oil is going thru the PCV line. GM did such a poor job on the PCV port and baffling on my 2006 Cadillac CTS that the catch can I put on it collects about 1.5 oz of oil every 100 miles on average. so essentially a half quart every 1000 miles. Kinda gives a different perspective on the idea of a fine mist.
 
Originally Posted By: Ohle_Manezzini
Originally Posted By: demarpaint
Originally Posted By: KevinP
I'm sure the DI issue will eventually get resolved. In the meantime, I'm happy to not have one.


That's exactly how I feel.


Dermapaint. Would that can dripping help in this gdi regard?


If you're referring to the Inverse Oiler, yes I think it would help. I'd try it with a mix of a UCL and Red Line FI cleaner, or straight Red Line FI cleaner. If blow by is a contributing factor to the deposit problem, then something good at cleaning deposits and carbon constantly metered slowly through the system via a vacuum line might just do the trick. An Inverse Oiler does that.

Just an FYI-Inverse Oilers don't clean fuel injectors on EFI engines.
 
Originally Posted By: rooflessVW
Originally Posted By: tig1
How do we know the picture of the valve deposits are really from an Ecoboost engine. Just askin.


Here you go, 15 pages...

Carbon Buildup Thread

I'm going to weigh in on this specific DI issue because I remember watching/following the topic on bitog with the eco boost introduction. After the first Ford 'torture test' of the ecoboost engine the Ford boosters I'll call them, pointed to the teardown results as proof the ecoboost had solved the DI valve deposit issue. I could likely find the thread but not the point. That said, not my intent to pick on one manufacturer. Just sayin.

Following on that, seems 'to me' from observation, which manufacturer is doing DI best now often depends on what brand/manufacturer one favors or uses. That said, some are likely doing it better than others now but none are likely as bad as the early adopters like VW/Audi.

And as noted here too, not sure with the latest generation DI how much the deposits are truly an issue in real world use. My .02
 
Originally Posted By: jaynissan12
I owned a frontier with the 4.0 direct injection engine.


From 2005 when the 4.0 (VQ40DE) came out in the Frontier, to 2016, Nissan has not put direct injection on this engine. They have a "direct ignition system" that I've seen some get mixed up with direct injection though.
 
We've owned our Hyundai for a year and 30k miles. Been one of the best vehicles we have ever owned. Runs perfect. In the last year I've run Techron twice, CRC cleaner once and used mostly top tier fuel. Still gets around 30mpg as it did when we first got it.
 
Originally Posted By: timeau
Originally Posted By: Carguy21
Well, Toyota is known for reliability, so now they are comming out with DI engines in many models, including some known for reliability like the Tacoma and RX350 - IMHO they took the carbon formation on the 2GR-FKS very seriously. Do any of you know what the did on that engine to prevent it if the did something?

These engines combines regular multipoint injection with DI. When strong acceleration is required, DI is used whereas relaxing cruising on highway activates MPI. So the buildup during DI is removed as before.


Believe that Toyota has a patent on the combined DI/MPI system, and it was used in the 2.0l engine for their FR-S/BRZ joint project with Subaru...but NOT in the 2.0l used in Subaru's Impreza and with a turbo added for the Forester XT and WRX (krapp!!!).
I read a claim a while back that Toyota is now allowing other makers to use their system royalty-free...wonder if that is true and how many other makers will bite if so.
 
Originally Posted By: novadude
As bad as those ecoboost valves in the picture above look, I have pulled apart MANY 60s-70's era small block Chevy engines that looked just as bad if not worse.

Sure, they might have been down on power, but not by any amount that was extremely obvious to the daily-commute driver. No apparent drivability issues with gunked up valves - they all started fine, idled fine, ran OK at part throttle around town, etc.

I'm not saying that these deposits are a good thing, but the people that shriek in horror at photos like the one shown above should remember that we've been living with IV deposits for many, many years.


I took a few apart myself, it takes way more miles for them to look as bad as some of these DI engines do in a such a short period of time. And like you said in spite of it the SBC still ran good.
 
A couple of points here.

1 - An inverse oiler or "dripper" may not work well on many modern engines due to the dry manifold design. This will more than likely result in very spotty delivery and some valves will get cleaned while others will not.

2 - While Toyota and others have added an injector or two to the manifold on a DI engine it was NOT for valve cleaning. A great side benefit that is not what most here think it is.

3 - People with the lead foot are unlikely to experience as many issues as those who soft pedal the car all the time. So get on it and your valves will be clean all the time!
 
Originally Posted By: Vern_in_IL
*sigh*

DI is NOT wonderful and it is not great. It is STUPID to have a "non perfected" system on the market(DI) a system you have to buy cleaning kits, increased warranties and maintenance, this is not great. Just a tech pushed on the market because (at the time) fuel prices were outrageous.

Why don't they use TWO injectors? a main DI injector, and a secondary traditional injector. (used in conjunction or as a maintenance instrument.!
I think I read an article where Ford is going to introduce a 5.0 DI with secondary injectors before the valves to help with the buildup on the valves.
 
Originally Posted By: Gillsy
Originally Posted By: Vern_in_IL
*sigh*

DI is NOT wonderful and it is not great. It is STUPID to have a "non perfected" system on the market(DI) a system you have to buy cleaning kits, increased warranties and maintenance, this is not great. Just a tech pushed on the market because (at the time) fuel prices were outrageous.

Why don't they use TWO injectors? a main DI injector, and a secondary traditional injector. (used in conjunction or as a maintenance instrument.!
I think I read an article where Ford is going to introduce a 5.0 DI with secondary injectors before the valves to help with the buildup on the valves.


One of these days they'll perfect the technology, just in time for the next latest and greatest.
 
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