Direct Injection Fouls Some Early Adopters

[Sayjac]

The article and comments by Tony Chick seems to indicate that progress has been made in the design of the breathing systems, pcv and egr. And, that has been able to reduce the deposits in more recent designs.

Direct Injection in Early Adopters

 

[Steve S]

Another article!!!! I'll still let others pay to work the bugs out before I buy one.

 

[Sayjac]

I hear ya, and why I chose a port injection vehicle for my recent vehicle purchase. But, if you read the article, it does appear progress has been made.

With the number of DI vehicles being sold, I believe it's here to stay, at least till something better comes along.

 

[demarpaint]

That 2012 Rubicon is looking better and better for me. I'd love to hold off till 2013 for $$ reasons, but run the risk of them wrecking the 3.6L Pentastar engine and changing it to DI.

I think DI perfection is still a few years away.

 

[T-Keith]

Sounds like the lowly American Manufacturers have it figured out and the German Manufacturers just getting there. Reminds me of the terribly complex and troublesome fuel injection systems VW/Audi had in the 80s, while GM had one of the most advanced SPFI systems in the 3800 and mass produced them without trouble.

 

[demarpaint]

Originally Posted By: T-Keith
Sounds like the lowly American Manufacturers have it figured out and the German Manufacturers just getting there. Reminds me of the terribly complex and troublesome fuel injection systems VW/Audi had in the 80s, while GM had one of the most advanced SPFI systems in the 3800 and mass produced them without trouble.


I have my doubts about GM having it worked out just yet either. Ford OTOH might, but their "torture test" tear down didn't represent soccer mom driving so IMO the jury might still be out for them as well. JMO

 

[Sayjac]

I'll say this, we may know more in a few years whether the recent generation of DI vehicles, are there now. Or, which ones if any, are there now. I found engineer Chick's comments to be positive on the recent/current generation of DI, as related to improved engine design and the pcv/egr systems.

 

[PZR2874]

Normal maint (Seafoaming) gets rid of it on the valves. And not driving it like a grandma helps as well.

I seafoam mine every thousand miles to combat this.

 

[demarpaint]

Originally Posted By: PZR2874
Normal maint (Seafoaming) gets rid of it on the valves. And not driving it like a grandma helps as well.

I seafoam mine every thousand miles to combat this.


That seems like a lot of extra work to maintain the system, and not "normal maint". JMO

 

[Jeff_in_VABch]

From the article:
“Gasoline engines with direct injection of the fuel into the combustion chamber…suffer especially from the problem of the formation of carbon deposits…especially in the neck region of the intake valves.”

"The document describes these deposits as a sticky coating of oil and fuel constituents that, once formed, serves as a base for further deposits, creating “a circular process, by which the coating thickness of the carbon deposits continuously increases.”

Well HELLO, that is the exact same process and area of the valve that has accumulated carbon since the Model T, not something special to DI.

Also, Volkswagen has never been able to engineer a product for durability, nothing surprising there. That VW DI engine is probably sealed with Indian Head sealant just like a 1300.

 

[demarpaint]

Originally Posted By: Jeff_in_VABch
From the article:
“Gasoline engines with direct injection of the fuel into the combustion chamber…suffer especially from the problem of the formation of carbon deposits…especially in the neck region of the intake valves.”

"The document describes these deposits as a sticky coating of oil and fuel constituents that, once formed, serves as a base for further deposits, creating “a circular process, by which the coating thickness of the carbon deposits continuously increases.”

Well HELLO, that is the exact same process and area of the valve that has accumulated carbon since the Model T, not something special to DI.

Also, Volkswagen has never been able to engineer a product for durability, nothing surprising there. That VW DI engine is probably sealed with Indian Head sealant just like a 1300.



What you say is true about the carbon to a point. DI seems to dilute fuel in many instances, and these valve deposits form very quickly many people are saying. The fuel issue has GM reprogramming their OLM system for DI applications, and many cars are in needed of cleaning of valve deposits very early in their lives. There is no doubt in my mind the technology is here to stay, there is also no doubt that there are problems that need to be ironed out still. JMO

 

[PZR2874]

Originally Posted By: demarpaint
Originally Posted By: PZR2874
Normal maint (Seafoaming) gets rid of it on the valves. And not driving it like a grandma helps as well.

I seafoam mine every thousand miles to combat this.


That seems like a lot of extra work to maintain the system, and not "normal maint". JMO


Not really. I buy the gallon and it lasts me a year+. Takes 15 minutes every month. Gives me piece of mind as well. COBB (Plano)was amazed at how the car ran with this many miles on it. So it must be helping to a degree. Anyone want to ship me a bore-scope?

 

[SteveSRT8]

Sure. And some of us would need to Seafoam every WEEK? Are you kidding me?

DI has a long way to go before people like me want one. Too many unanswered questions.

 

[Steve S]

Back in probably 1985 taking my continueing auto education classes I remember a BMW tech explaining the process of media blasting the intake valves due to "carbon" buildup. The problem will be worked out eventually and I will thank all those who paid for the developement of the product.

 

[Steve S]

Originally Posted By: Jeff_in_VABch
Also, Volkswagen has never been able to engineer a product for durability, nothing surprising there. That VW DI engine is probably sealed with Indian Head sealant just like a 1300.

That is referred to by those in the know as fine German engineering.

 

[demarpaint]

Originally Posted By: SteveSRT8
Sure. And some of us would need to Seafoam every WEEK? Are you kidding me?

DI has a long way to go before people like me want one. Too many unanswered questions.


My feelings EXACTLY!!!!!!

 

[PZR2874]

I just don't see the issue with doing it on a regular basis. I have always (8-10 yrs) felt a difference in the car I've had at the time after the treatments.

TETO

I can't see doing it weekly as you would just be destroying your oil.

 

[SteveSRT8]

sorry man, but I own vehicles that see that many miles every week all year! (I'm a fleet owner)

That's why I made the comment. Make sense now?

 

[PZR2874]

^^ Yep.

And they are all DI'd engines?

 

[OVERKILL]

Originally Posted By: T-Keith
Sounds like the lowly American Manufacturers have it figured out and the German Manufacturers just getting there. Reminds me of the terribly complex and troublesome fuel injection systems VW/Audi had in the 80s, while GM had one of the most advanced SPFI systems in the 3800 and mass produced them without trouble.


Ford also had an excellent early system: the EEC-IV SEFI system with individual injector drivers and then mass air as early 1988.

The system was developed in conjunction with Bosch (uh oh, those rascally Germans!) and Intel.