Deposts on DI engine valves

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I recall that in early direct fuel injection (DI) engines there was a significant problem with fuel deposits on intake valves. There was discussion that this required very frequent oil changes to counter this. My question: Has this problem been solved? Is there still a problem of fuel deposits on the intake valves of direct injected engines? It seems that most cars I'm considering to buy all have the DI motors.
 
Direct Injection hasn't been perfected yet, but such new vehicles equipped with it are doing better, sometimes a much better job today handling intake valve deposit than early adopters that bought an Audi with it a decade ago.
The people that have had issues with intake valve deposits in my opinion are easy going drivers. If you get a new Acura with a direct injected V6 and only drive it to church or the store a mile away all the time, expect problems eventually. Take the same vehicle, drive it with passion and let the engine get warmed up every time you go somewhere and you might never have an issue, even if you put 200K on it.
 
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Depends on a particular DI engine. Some seem to suffer more than others.

And no, frequent oil changes don't really help, AFAIK.
 
Use of low SAPS oils contribute to less deposites...

And also if you use (purpose) valve cleaners (additive)...or premium gas with them already...
 
I just recently saw an episode of motorweek where the mechanic on there put a pcv catch can on a new camaro. He said if you drive aggressively that it will save you a lot of money in the long run having one on a direct injected engine.
 
Originally Posted By: Quattro Pete
Depends on a particular DI engine. Some seem to suffer more than others.

And no, frequent oil changes don't really help, AFAIK.


+1 They've come a long way. Frequent oil changes might help with fuel dilution, another problem some DI engines were plagued with, but it won't help with the carbon problems on the intake valves some of them have.
 
Originally Posted By: Mr Nice
Which manufacturer is the worst for DI problems ?


Probably Audi/VW.

They're still extending warranties because of lawsuits related to excessive deposition of carbon.
 
Engines with both DI and turbocharging seem to have it worst. Catch cans do not always solve the problem. For example, when the the source of the problem is oil making its way by valve seals the catch can is ineffective.
I have yet to see real evidence that driving a car hard will prevent or remove intake valve deposits. Making sure that the car is driven most of the time at the designed, steady state hot, oil temperature is always a good advise though.
 
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I'm not going to bash DI since some users on here may call me backwards or an old dinosaur for not embracing these new technologies.

DI is wonderful! It's great! Just like car infotainment screens being integrated with Twitter and Facebook!
 
Originally Posted By: Kamele0N
Use of low SAPS oils contribute to less deposites...

And also if you use (purpose) valve cleaners (additive)...or premium gas with them already...


Gasoline additives don't do anything for carbon buildup on DI engines, the gasoline never washes over the valves.
 
*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.!
 
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Wide soread grades i.e. 5w40 like vw says, some not 502.xx or 505.xx maybe loaded with VII that end up building crude at hot shutdown leak past guides and consequent burn phase. Maybe a good 10w30 would keep the valves cleaner for a longer time?
 
My malibu is DI, i didnt realize tht till after i bought the car. I bought an extended warranty so hopefully this car can last me.
 
My old 2007 CX7 Mazda with DI and turbo was running great, like new at 81,000 miles when I traded it for a new Mazda DI. With few exceptions, I think the bad mouthing of DI is way overrated. Ed
 
Originally Posted By: Vern_in_IL
...

Why don't they use TWO injectors? a main DI injector, and a secondary traditional injector. (used in conjunction or as a maintenance instrument.!


Some are starting to....it is the common sense solution to all the issues. I am sure there will be teething problems with the new more complex electronics....
 
Originally Posted By: dmdx86
Originally Posted By: Kamele0N
Use of low SAPS oils contribute to less deposites...

And also if you use (purpose) valve cleaners (additive)...or premium gas with them already...


Gasoline additives don't do anything for carbon buildup on DI engines, the gasoline never washes over the valves.


I have to wonder how much PEA is able to get routed past the intake valves due to EGR.
 
I don't have a DI car yet, but the whole industry is moving on that direction (and more turbos are showing up), so in some years, we all probably are going to have a DI vehicle and maybe with a turbo. The carbon formation is something that the manufactures have to target seriously and find a solution.

My question is, what is the best way to avoid the carbon formation on the DI engines? if there is something the owner can do.
 
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