Turbo vs. Direct Injection which is more reliable?

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With so many cars being equipped with DI/ Turbocharged (Ecoboosted for Ford)these days, which is more reliable over the long term?

The DI issues I've heard of include carbon buildup. Is this common on ALL DI equipped vehicles as they age? or only early adopters of the technology?

From my understanding most turbo equipped vehicles since the late 2000's all are fairly reliable. Most regularly maintained models never have reported issues past the 100k mile range (fairly stout given the performance gains).

Personally I'm reluctant to adopt either of these technologies. But considering how mainstream they are becoming means that I might have to make a choice sooner or later.
 
The way you phrase the question it almost sounds like you believe the two are mutually exclusive--like you can have one or the other, but not both DI and a turbo. That's not the case, and one has nothing to do with the other. Both are well proven and established technologies. I wouldn't hesitate to buy a vehicle with either, or both. To be honest, neither would really factor into my buying decision.
 
When KIA went DI ..... they lost my business.

When Chevy went Turbo on econoboxes which don't obviously get their oil changed regularly..... they lost my business.

Eventually when Toyota looses their common sense and only offers DI, Turbo and CVT powertrains... they 'll loose my business. I suppose I will then make it the last third of my life keeping up some old '05-'15 Toyota rolling stock.
 
Originally Posted By: SumpChump
When KIA went DI ..... they lost my business.


Have you ever owned a KIA?
 
Originally Posted By: SumpChump

...
When Chevy went Turbo on econoboxes which don't obviously get their oil changed regularly..... they lost my business.
...


I guess this doesn't make much sense to me. I'm responsible for oil changes for every vehicle I own, so if I slack off on it, I'm certainly not going to blame the manufacturer.
 
Originally Posted By: SumpChump
When Chevy went Turbo on econoboxes which don't obviously get their oil changed regularly..... they lost my business.

So you're blaming Chevy for not getting your oil changed regularly???
 
Originally Posted By: SumpChump
When Chevy went Turbo on econoboxes which don't obviously get their oil changed regularly..... they lost my business.


Way to be the reason the Cruze got a bad wrap, and way to be the change you wish to see in the world. Trucks are engineered for way more abuse than cars, bumper to bumper - shouldn't they be the ones getting less religious maintenance? Oh, nevermind - spend 20K on an econobox and it's a "throwaway", so why even try regardless of whether it actually is or not?

IMHO I'd put DI as the generally less dependable/trouble free technology. It seems all other things being equal a turbo car can last just as long with just as short a repair record as any other car... unless you treat it like an old Accord with 10K conventional OCI's and then it ain't gonna be as forgiving as the Honda.
 
Being that the scale goes from mutually exclusive to older, problematic designs, I wouldn't have the nut to make a blanket statement. I think it really depends on the maker, design, and other factors in order to try to parse out which is more dependable, reliable, or what other word you want to use...and what that word means to you.

IMO, this site has a lot of inordinate fear of DI so you're possibly going to have responses that are skewed to that fear and dislike versus your or others actual experience with a DI car ( NA or turbo ) if you owned one. I have a small 2013 NA engine DI car that I do exactly what the manufacturer wants me to do and use further information that I get here. No issues and runs great. Friends have DI cars with 100K plus miles on them with no issues. The world isn't ending and if you want to make your stand against DI then that's your prerogative...you're not exactly an early adopter at this point but some folks on here still want to wrap themselves in that robe.
 
They put a same sized GDI engine in the latest generation of Hyundai Accent and ruined the car IMHO. More power you don't need unless you have an automatic and less gas mileage as well as the usual GDI intake valve build up.

And now you can't even get the manual 6sp in the sport edition....
 
Both technologies are very reliable on a day to day basis. Sure you might have to do a deposit clean up at some point. Maybe you need a new turbo after 100k miles. You could call these things maintenance more than that failures.

N/A Port injected engines won't need these "maintenance" items. I'm willing to accept the maintenance for the power and fuel economy DI and DI-T engines offer.
 
Originally Posted By: SHOZ
They put a same sized GDI engine in the latest generation of Hyundai Accent and ruined the car IMHO. More power you don't need unless you have an automatic and less gas mileage as well as the usual GDI intake valve build up.

And now you can't even get the manual 6sp in the sport edition....


I would disagree...I actually run a 2013 Accent 6 spd. manual as my commuter module and I can tell you, having driven an older one, it has considerably more power and gets significantly better MPGs than the previous generation. I've done hand calculated 40 mpg highway trips on more than one occasion and I'd have serious doubts that the previous generation would be able to replicate that very often. No GDI-related issues to this point. Hyundai says the RB Accent ( 2012- ) should get about 18% better mileage than the previous version. IMO, that's probably accurate.

I absolutely agree with you though about availability of the manual in the top spec...and, at last count, the redesigned 2018 hatch is apparently going to be Canada-only...both bad moves as far as I'm concerned.
 
The turbo DI four in my MS3 hit 158k with no major issues. Never had any deposits removed either. My current DD is a turbo/DI inline six and I lose absolutely no sleep over adopting the technology.
 
Originally Posted By: dareo
Both technologies are very reliable on a day to day basis. Sure you might have to do a deposit clean up at some point. Maybe you need a new turbo after 100k miles. You could call these things maintenance more than that failures.

N/A Port injected engines won't need these "maintenance" items. I'm willing to accept the maintenance for the power and fuel economy DI and DI-T engines offer.


I'm sure the math isn't too hard to do on this, tedious probably, but I wonder what the payoff really is. Say you get an N/A non-DI car that gets 30mpg (87 octane), and a turbo DI car that gets 35mpg (93 octane). But the DI car will need deposits cleaned and a turbo goes bad just out of warranty. turbo, say $1000, $500 for cleaning? at 65k miles, which is cheaper to run factoring in $1500 for turbo-DI work, and what 50 cents more per gallon on premium?

Rough numbers say....
$5416.66 for N/A car (2.50 a gallon)
$5571.43 + $1500 = $7071.43 for turbo-DI (3.00 a gallon).

Really rough numbers and I did that quickly. Not a turbo-DI hater, I have one. But I do wonder the lifetime savings of such tech, when you factor in specific issues to that tech (all other things equal). But as it gets more reliable those extra maintenance costs will drop I'm sure.
 
Originally Posted By: HemiHawk
But as it gets more reliable those extra maintenance costs will drop I'm sure.


Plus buying an NA non-DI engine may not even be an option pretty soon.
 
DI means direct ignition. That is a Saab proprietary innovative ignition system with one coil for each cylinder packed into a cassette above the spark plugs, which uses ion flow measurement in the plasma surrounding the spark plug to detect knock. This allowes to monitor the combustion in each cylinder separately, and thus adjust timing for each cylinder individually. Each charge can thus be ignited with optimum timing, riding the very sharp edge just before knock would occur.

DI was introduced on the B202XL engine in the Saab 9000 turbo in model year 1989, and the two different versions (red and black, interchangeable only in emergencies) have been fitted to most Saab H engines since. The system is generally considered reliable, with the assumption that ist works flawlessly until it doesn't. Lifespan of genuine (SEM and NGK) DI casettes vary between 250.000 and 350.000km. Cheaper knock-offs have been known to fail earlier. Cassettes cost a few hundred euros, but can be changed within a few seconds, which is why experienced Saab drivers have a used, but known to be still working spare cassette in the trunk once the cassette on the engine reaches a critical age. Addition of spare cassette to trunk extends life of engine-mounted cassette indefinitely.
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What most people mean when using the acronym DI (incorrectly!) is direct injection, where,in contrast to port fuel injection, fuel is delivered directly into the cylinder. Direct injection allows both higher compression ratios and less enrichment under full load, both of whih increase efficiency significantly. Common issues that may arise are LSPI, or, when the manufacturer avoids LSPI-conditions, fuel dilution; plugged dinjectors (which may lead to other symptoms ranging from bad throttle response and reduced power to holes in piston) and coked-up intake valves (which are no longer cleaned by fuel sprayed onto them, like with a port fuel-injected system.)
Direct injection may or may not be reliable and durable. I'd trust Toyotas and Subarus with their D4S-system (which combines both systems), I'd not necessarily trust other manufacturers and I do NOT trust VW and Audi especially.

Turbocharging is rather old stuff. The turbocharger was invented somewhat around 1905, if I recall correctly. It has been used on airplanes sine WWII, and on diesel engines since practically forever. Pioneers regarding it's use in passenger cars were Chevrolet (corvair), BMW and Saab, the latter being the first to use turbochaging not to increase peak power, but mid-range torque, thus inventing the concept that would late become known as downsizing. That was in the mid-70s. Since the introduction of the electronic boost control in 1982, turbocharged petrol enengines have become as reliable and durable as the best naturally aspirated engines when properly operated and maintained. Turbocharger failures and engine failures on turbocharged engines can usually be attributed to user error, ignorance, neglect, and/or stupidity.
Turbocharging can be combined with any way of fuel delivery, ranging from carburettors and port-fuel-injection to direct injection.


So... to make a long story short, it is much more important who builds an engines than wich technology/alpahbet soup the engine uses. If you are incompetent or cheapskate enough, you can [censored] up even the most mundane construction, while others can make complicated and advances stuff that is reliable and lasts...
 
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I have co-developed a quality study that looks at the long-term reliability of used cars. We have over 1.4 million vehicles that are inspected by ASE certified independent mechanics.

http://www.dashboard-light.com/

The only manufacturer that even approaches average reliability with direct injection engines is Lexus. Every other brand that offers DI is well below average.

As for turbos, the one that's furnished for the Cruze is primarily responsible for its low long-term reliability rating. However there are plenty of sports cars and roadsters that have turbochargers and outstanding reliability.

The same is true with superchargers. There's a lot more depth to this information, but what I can comfortably state here is that turbocharging is not a negative factor in the longevity of vehicles if it's a quality component that has been well kept by the owner.

Hope this helps.

Steven Lang
 
Both are fine as long as you change the oil according to the manual with an approved oil. Use top tier gas as well. So many people are afraid that DIs or turbos are garbage. There are plenty on the road with many miles working just the way they were intended. I wouldn't think too hard about it.
 
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