Direct injection and a long living healthy engine

Have the same questions because of the truck we recently got. Along with using syn oil and good gas and the occasional high rpm run-up choosing oil with low NOACK numbers can't hurt and some guys install a catch can in the PCV circuit to clean up the gasses before reaching the intake. Might not be necessary but can't hurt either.
 
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Central Maryland
Originally Posted By: Iowegian
Depends. Not sure about Ford.
You can count on Ford to screw their customers. Just look at: Triton spark plug holes stripping out (round I), Triton spark plug break-offs (round II), PowerStroke 6.0L. If it's a Ford engine problem, it's your problem.
 
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28,125
Location
Regina, Saskatchewan, Canada
Originally Posted By: double vanos
A DI engine that's "aired out " regularly is a happy DI engine.
That seems to be true, but it does point out the folly of how regulations are brought about and enforced. Let's use a technology that gives us better fuel economy to pass testing, yet, in the real word, works best when driven in a way that produces the worst fuel economy possible.
 
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New England
Subaru sells a cleaning tool kit and a couple of different cleaners to be introduced through a vacuum hose, I'm hoping to try one of the cleaners this weekend (I bought both types, top engine cleaner and carbon clean). I tried introducing a CRC spray cleaner through the open airbox and that didn't go so well, ended up having to clean my MAF sensor and I suspect that the cleaner pooled up somewhere based on the way my car acted just after the process. The nozzle of the spray can was past the MAF, but I think there must have been some backspray. My car did run incredibly well after I cleaned the MAF, though, but I don't now if it was from the valves getting cleaned or me getting already existing gunk off the MAF (or just completely my imagination).
 
Originally Posted By: Garak
Originally Posted By: double vanos
A DI engine that's "aired out " regularly is a happy DI engine.
That seems to be true, but it does point out the folly of how regulations are brought about and enforced. Let's use a technology that gives us better fuel economy to pass testing, yet, in the real word, works best when driven in a way that produces the worst fuel economy possible.
My understanding is high rpms creates such high acceleration/de-acceleration forces on the valves it loosens the carbon and it falls off. Doing this occasionally for short periods probably doesn't have much effect on overall fuel economy. Agree with your premise about the folly in general.
 
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Middle of Iowa
Originally Posted By: benjy
DI engines DO NOT clean the valves with fuel or any other additives as it injects directly into the combustion chamber! parts if needed will be more costly but there are VERY FEW non DI engines today. early ones had the most problems + turbo charged engines were worse. hopefully they are getting better for my girlfriends sake, i own none. slower short trips are said to build carbon quicker as well. good luck!!
I don't know that this is 100% true. There is evidence that the Mercedes 3.5L in my ML350 has the ability for the direct injector to spray at least part of the back of the intake valves. The injector is aimed in such a way that when the intake valves are wide open the spray pattern may overlap part or most of the back side of the intake valve. I don't think it does this all the time, but rather a limited amount of time. This is further supported by the distinct different operating sounds of the engine. I had the car running in the garage after an oil change, and it sounded like a loud DI engine normally does (almost diesel like). Then it just suddenly switched and started sounding totally different...much smoother. I don't know if it was switching between a normal mode and a cleaning mode, but I have noticed this several times when my wife actually lets me drive her car. This coupled with not a single report I can find on this engine and carbon problems leads me to believe they may have found a way to get the DI injector to spray at least a little bit on the backs of the valves.
 
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Canuck living in California
Intake valve deposits bother the anal retentive people on the internet, that's about it. The rest of the driving public doesn't have a clue how the fuel is being injected into the combustion chambers, for them it may as well be magic. Only in the most severe of cases the deposits will cause problems, like a misfire. These cases are quite rare. However, fuel dilution would be something to take note of. Still, not a big deal with regular and not super long oil changes.
 
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Texas
My 2008 Cadillac CTS with the 3.6L DI engine just turned 135k miles and all is well. Mom has the same car but with 86k miles and no issues.
 
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28,125
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Regina, Saskatchewan, Canada
Originally Posted By: AZjeff
My understanding is high rpms creates such high acceleration/de-acceleration forces on the valves it loosens the carbon and it falls off. Doing this occasionally for short periods probably doesn't have much effect on overall fuel economy. Agree with your premise about the folly in general.
And they wonder why cheating happens. wink
 
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17,718
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NH
Originally Posted By: OneEyeJack
Soon, everything will be DI and with all the expertise available and feed back it's going to get handled. A mass produced internal combustion engine is already an engineering and manufacturing marvel. Things we expect and take for granted did not start that way.
I think this is true. Everything starts someplace, usually as "lousy" and "expensive to fix". Yet after enough of them are out there it becomes the new normal. I bet CVT's will eventually get there too. wink
 
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35,621
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NY
Originally Posted By: supton
Originally Posted By: OneEyeJack
Soon, everything will be DI and with all the expertise available and feed back it's going to get handled. A mass produced internal combustion engine is already an engineering and manufacturing marvel. Things we expect and take for granted did not start that way.
I think this is true. Everything starts someplace, usually as "lousy" and "expensive to fix". Yet after enough of them are out there it becomes the new normal. I bet CVT's will eventually get there too. wink
DI and CVT..... hide Like it or not.
 
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393
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queens
Originally Posted By: MCompact
I drove a 2007 Mazdaspeed 3 for 158k miles. No complaints. I now have to DI vehicles in the garage, one with over 100k; I don't lose one nanosecond of sleep over the technology.
Same here. Lots of fear about carbon buildup on over at the Subie forums and the FA, not worried at all. I prefer (potential) carbon buildup over ringland failure. coffee
 

CKN

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6,333
Location
Utah
Originally Posted By: demarpaint
Originally Posted By: supton
Originally Posted By: OneEyeJack
Soon, everything will be DI and with all the expertise available and feed back it's going to get handled. A mass produced internal combustion engine is already an engineering and manufacturing marvel. Things we expect and take for granted did not start that way.
I think this is true. Everything starts someplace, usually as "lousy" and "expensive to fix". Yet after enough of them are out there it becomes the new normal. I bet CVT's will eventually get there too. wink
DI and CVT..... hide Like it or not.
BITOG fear mongering at it's finest on this site. Time to go by that 15 year old Crown Vic or 10 year old Ford Taurus. None of those fancy gadgets on those cars......
 
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17,718
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NH
Originally Posted By: CKN
BITOG fear mongering at it's finest on this site. Time to go by that 15 year old Crown Vic or 10 year old Ford Taurus. None of those fancy gadgets on those cars......
Not sure what you are upset about. I like to drive, and drive lots, but I don't want to do repairs. I usually buy for 10+ years, which means 250k is an expected number. When trying to project TCO on a vehicle... why would I gamble on something unknown? Today I might be willing to buy DI (maybe even CVT!) since it's finally gotten proven. But I don't feel like being an early adopter. What's wrong with being a cheapskate? shrug
 
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5,348
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down in the park
Originally Posted By: Garak
Originally Posted By: double vanos
A DI engine that's "aired out " regularly is a happy DI engine.
That seems to be true, but it does point out the folly of how regulations are brought about and enforced. Let's use a technology that gives us better fuel economy to pass testing, yet, in the real word, works best when driven in a way that produces the worst fuel economy possible.
Not quite: if you choose a smaller engine, you need to air it out just to keep up with speed limits, and you'll definitely reduce pumping losses that way.
 
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1,515
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California
I'm just glad that it seems BITOG has gotten away from blanket statements about DI...some more in sync with 2007 than 2017. My experience in having no issues with a five year old DI car and two co-workers who have over 150K on theirs with no DI/combustion-related issues tell me we're not an anomaly. At this point, it might be hard to call someone buying one an "early adopter" with a straight face.
 
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35,621
Location
NY
Originally Posted By: CKN
Originally Posted By: demarpaint
Originally Posted By: supton
Originally Posted By: OneEyeJack
Soon, everything will be DI and with all the expertise available and feed back it's going to get handled. A mass produced internal combustion engine is already an engineering and manufacturing marvel. Things we expect and take for granted did not start that way.
I think this is true. Everything starts someplace, usually as "lousy" and "expensive to fix". Yet after enough of them are out there it becomes the new normal. I bet CVT's will eventually get there too. wink
DI and CVT..... hide Like it or not.
BITOG fear mongering at it's finest on this site. Time to go by that 15 year old Crown Vic or 10 year old Ford Taurus. None of those fancy gadgets on those cars......
No fear mongering, and no need to buy a 15 year old Crown Vic or a 10 year old Taurus for me. I can easily buy a new 2017 vehicle that I like, very much in fact, and not have to buy CVT or DI. A GC Trailhawk, or a Ram PU come to mind. Funny you mention the Crown Vic, they have a great reputation for vehicles that last a very long time. wink
 
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