Direct Injection-Is it a good thing?

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Originally Posted By: RISUPERCREWMAN
I would stay far away from direct injection engines until the technology addresses the negative "Side Affects" . Don't even get me started on the Ford Ecodoom motors!


Actually, Ford and GM have had very few problems with their DI engines....It's Audi, VW etc..., and some of the Japanese that have needed expensive intake valve cleanings.

Except for the horribly unreliable A/T in the latest gen Focus, Ford seems to be making very good vehicles.
 
I'm in the anti DI camp until the carbon thing gets figured out. I'm worried about the CX 5, but we shall see.

And for those saying Chevy DI is not bad, check out the Camaro/Cadillac forums and the 3.6L engine.
 
Originally Posted By: RISUPERCREWMAN
I would stay far away from direct injection engines until the technology addresses the negative "Side Affects" . Don't even get me started on the Ford Ecodoom motors!


You can say that again! I sold my eight year old GDI turbo Mazdaspeed 3 with only158k miles on it. Despite the fact that I never had the valves cleaned there was no degradation of either drivability or performance. That said- I was certain that the other shoe was about to drop- that is why I replaced it with another GDI turbo.
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Direct injection is a series of compromises, as is everything else. You have go deal with carbon deposits, but you gain power and efficiency.

With port injection, you don't have to worry about carbon deposits, but you lose power and efficiency.

I'd be willing to bet that if you averaged out the costs between the two, you would just be spending your money in different places; I don't think it would be any less or more.
 
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Run Euro oil in it with NOACK less then 10%. How would you know? It should have on back side MB 229.5 specification.
Personally, I would run in that car Castrol 0W30 or Mobil 1 0W40 FS which in new formulation is very close to be 0W30 oil (12.6cst).
When you warm up oil in a car drive like you stole it.
 
Its great for a car that is < 7 years old. After that, sell it before the turbo explodes or the head chokes on its own vomit.
 
When I was in uni in the late '80s, DI was "just around the corner", and was going to be all things to the industry.

But industry seems to have let their execution not live up to their promise.

Fuel dilution and LSPI indicate that the fuel is hitting the cylinder walls, mixing with it, then either heading for the crankcase, or revolatising off as an autocombustibe vapour/mist around the compression rings.

Dilution of the cylinder wall oil film is not a recipe for longevity, nor is blowing off ring lands.

Diluting and evaporating the oil on the walls leads directly to emission system contamination of phosphorous.

Can only conclude that the application of the technology is poor.

Remember, D.I. has been very very common in diesels, and it's not plagued with fuel dilution and LSPI.
 
Haha, I prefer a good 'ol carburetor, an distributor ignition with points/condeser with both mechanical advance and vacuum advance. I love setting the dwell myself.

We have a number of vehicles with direct injection, none of them are problematic in any way. All of them perform quite well and return excellent fuel economy.

The reason I brought up the silly example above, is that was the argument used by many to justify their love for what was clearly (even then) sub standard equipment.
 
Originally Posted By: Cujet
Haha, I prefer a good 'ol carburetor, an distributor ignition with points/condeser with both mechanical advance and vacuum advance. I love setting the dwell myself.

We have a number of vehicles with direct injection, none of them are problematic in any way. All of them perform quite well and return excellent fuel economy.

The reason I brought up the silly example above, is that was the argument used by many to justify their love for what was clearly (even then) sub standard equipment.


Early electronic ignition had to evolve, as did fuel injection, as does DI. As time went by each of those systems improved. DI will improve as well. When it gets as good as it can get something will be there to replace it, and the cycle will start over for the evolution of the next latest and greatest automotive innovation.
 
Originally Posted By: Shannow
When I was in uni in the late '80s, DI was "just around the corner", and was going to be all things to the industry.

But industry seems to have let their execution not live up to their promise.

Fuel dilution and LSPI indicate that the fuel is hitting the cylinder walls, mixing with it, then either heading for the crankcase, or revolatising off as an autocombustibe vapour/mist around the compression rings.

Dilution of the cylinder wall oil film is not a recipe for longevity, nor is blowing off ring lands.

Diluting and evaporating the oil on the walls leads directly to emission system contamination of phosphorous.

Can only conclude that the application of the technology is poor.

Remember, D.I. has been very very common in diesels, and it's not plagued with fuel dilution and LSPI.

Culprit is in NoX regulations in the U.S. In Europe DI engines are using lean burn, much more refined injection process while in the U.S. to lower NoX stratified burn is used.
Diesels are plagued with fuel dilution, but diesel fuel is actually oil
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The solution is in HWY driving and aggressive driving. These engines do not have issues in Europe as much as here, since speeds are higher and people generally like to utilize car for longer driving, while in the U.S. cars serve mostly for city commute and Southwest for anything longer the 2hrs drive!
 
I've got a 2008 Cadillac CTS with the 3.6DI. I've got 117k miles with no issues other than the well known timing chains that were replaced under the customer satisfaction warranty. Smooth power all the time. I've seen no issues with carbon. I do spray a can of carb/intake cleaner thru the intake at each oil change as a preventative measure. My mom has the same year and model CTS with 87k miles and been good as well (timing chains were done also) and it's never had an intake cleaning. Looking thru the internet I've not seen concerns on GM DI systems.
 
134,000 on the Traverse, no DI issues. More worried about the timing chains, but so far no problems with those (knock on wood). When I did the spark plugs at 100,000 I eyeballed the intakes and they had no significant deposits.
 
Originally Posted By: Oldmoparguy1
I'm trying to understand just how DI is better then port injection..


Better control in general. I believe stratified charge went away, but it seems like one could inject towards the plug for the same idea.

Hot Rod magazine said it had a big impact on startup emissions. On port injection it has to run richer to start. Am guessing having the injector that much farther away also impacts response time.
 
Originally Posted By: Oldmoparguy1
I'm trying to understand just how DI is better then port injection..


Also, DI works well with high boost turbocharged engines, as the fuel is not injected until just before it's needed. Strongly reducing detonation and improving volumetric efficiency. DI allows Ford, for example to run very high boost on regular gas, produce excellent power and good fuel economy. The 2.7L Ecoboost F150 engine does perform quite well. Driven responsibly, they also return excellent MPG.

My 2009 5.4L V8 is slower than friend 2016 2.7 Ecoboost. I get 14.5MPG, he gets 20+ , same commute.
 
Originally Posted By: Cujet
Originally Posted By: Oldmoparguy1
I'm trying to understand just how DI is better then port injection..


Also, DI works well with high boost turbocharged engines, as the fuel is not injected until just before it's needed. Strongly reducing detonation and improving volumetric efficiency. DI allows Ford, for example to run very high boost on regular gas, produce excellent power and good fuel economy. The 2.7L Ecoboost F150 engine does perform quite well. Driven responsibly, they also return excellent MPG.

My 2009 5.4L V8 is slower than friend 2016 2.7 Ecoboost. I get 14.5MPG, he gets 20+ , same commute.


We just bought a '16 F150 with the 2.7 ecoboost and I've found that my wife likes the boost gauge displayed in the dash cluster. I asked her of all of the different things that could be displayed why she chose the boost, her response was that she liked to see how high it would go when someone tried to get her off the line after waiting on a red light on her way to/from work!

Evidently she feels that both turbos need exercised on a regular basis.

As of now it has less than 1,000 mi., I filled it up tonight and shes getting 19 mpg commuting to/from work which is fairly impressive with all of the "exercise" the turbos are getting.
 
Originally Posted By: roadrunner1
Originally Posted By: Cujet
Originally Posted By: Oldmoparguy1
I'm trying to understand just how DI is better then port injection..


Also, DI works well with high boost turbocharged engines, as the fuel is not injected until just before it's needed. Strongly reducing detonation and improving volumetric efficiency. DI allows Ford, for example to run very high boost on regular gas, produce excellent power and good fuel economy. The 2.7L Ecoboost F150 engine does perform quite well. Driven responsibly, they also return excellent MPG.

My 2009 5.4L V8 is slower than friend 2016 2.7 Ecoboost. I get 14.5MPG, he gets 20+ , same commute.


We just bought a '16 F150 with the 2.7 ecoboost and I've found that my wife likes the boost gauge displayed in the dash cluster. I asked her of all of the different things that could be displayed why she chose the boost, her response was that she liked to see how high it would go when someone tried to get her off the line after waiting on a red light on her way to/from work!

Evidently she feels that both turbos need exercised on a regular basis.

As of now it has less than 1,000 mi., I filled it up tonight and shes getting 19 mpg commuting to/from work which is fairly impressive with all of the "exercise" the turbos are getting.

I would be easy with that exercise first 5K.
 
Originally Posted By: roadrunner1

We just bought a '16 F150 with the 2.7 ecoboost and I've found that my wife likes the boost gauge displayed in the dash cluster. I asked her of all of the different things that could be displayed why she chose the boost, her response was that she liked to see how high it would go when someone tried to get her off the line after waiting on a red light on her way to/from work!

Evidently she feels that both turbos need exercised on a regular basis.

As of now it has less than 1,000 mi., I filled it up tonight and shes getting 19 mpg commuting to/from work which is fairly impressive with all of the "exercise" the turbos are getting.


It's funny isn't it ?

My wife asked me what I'd done to the Caprice one evening..."it seems a bit more peppy".

I'd dropped pulley size on the supercharger from nominal 6 to 10psi boost.

Turns out that she was first at the lights, when a P-Plater pulled up in the turn only lane, obviously with intent to cross the intersection and cut her off...she had to throttle off a little to control the wheelspin, where she "didn't have to before"...
 
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