Direct Injection Engines

[caprice_2nv]

Originally Posted by BMWTurboDzl
Originally Posted by Al
With DI engines becoming more common, there is increasing concern about carbon buildup underneath the valves.


No there isn't. It ain't 2008.


?? What are you smoking? You seriously think there is no issues with direct injection?

 

[Silk]

Mitsubishi was making GDI engines in the '90's...and golly, they had intake deposit issues. They developed this stuff, best stuff ever for cleaning GDI intakes.

 

[Al]

Originally Posted by caprice_2nv
Originally Posted by BMWTurboDzl
Originally Posted by Al
With DI engines becoming more common, there is increasing concern about carbon buildup underneath the valves.


No there isn't. It ain't 2008.


?? What are you smoking? You seriously think there is no issues with direct injection?

lol..I first thought you thought "I" was smoking

 

[caprice_2nv]

Originally Posted by Al
Originally Posted by caprice_2nv
Originally Posted by BMWTurboDzl
Originally Posted by Al
With DI engines becoming more common, there is increasing concern about carbon buildup underneath the valves.


No there isn't. It ain't 2008.


?? What are you smoking? You seriously think there is no issues with direct injection?

lol..I first thought you thought "I" was smoking

Lol no. In 2008 I didn't know about any issues with direct injection because it wasn't very common back then.

 

[BMWTurboDzl]

Originally Posted by caprice_2nv
Originally Posted by BMWTurboDzl
Originally Posted by Al
With DI engines becoming more common, there is increasing concern about carbon buildup underneath the valves.


No there isn't. It ain't 2008.


?? What are you smoking? You seriously think there is no issues with direct injection?



With regards to your specific concern, yes. Drive-ability problems resulting from excessive carbon buildup on the back sides of the valves has largely become a non-issue. The presence of buildup doesn't mean there's a problem. Over the past decade or so manufacturers have implemented new technology to significantly reduce the rate of buildup or prevent it all together. For example back in 2008 the BMW N54 and I believe an Audi V8 were suffering from buildup related problems. Dealers were having to clean the valves every 40k miles. BMW "fixed" the problem when they introduced the N55 (2009) with a revised crankcase ventilation design. Owners peeking behind the intakes on high mileage (100k+) N55 engines are not seeing anywhere near the level of buildup that occurred on the N54 at 40k miles.

 

[Vuflanovsky]

At this point, I think you can probably say that there are still people on here that will co-opt any "fear porn" about DI into their view that doesn't represent the reality of the vast majority of current owners with these engines...Natch that's especially true if they don't own one and pontificate about them as offended experts who will never own one. They'll still call people early adopters when DI becomes 80% of the new car market and had been the majority of engines produced for a decade. The clock will be stuck in 2007.

You'll always have people on here wanting to get 350K miles out of their '70 Chevelle rather than buy a new car...unfortunately, some of these people seem to confuse that sentiment with keeping up with the current state of direct injection engines and view everything related to DI as the the worst VAG/BMW DI engine experiences from 2007. DI will always be X and will never change to Y whether that involves willful ignorance or not. Thankfully, that's rarer on here than it used to be....

 

[caprice_2nv]

I'm sure they aren't all problematic but certain models under certain circumstances are. My girlfriend has a 2013 Hyundai Sonata with the 2.4gdi. She has followed the owners manual recommendations as far as adding a fuel system cleaner roughly every 15,000kms. It has 102,000kms now (62k miles) and has very noticeable pinging under light load. It's going to stay that way because she doesn't believe in over doing maintenance like I do on my ancient 83 and 84 cars. The vast majority of owners are like her, so the car is going to keep pinging and they won't even take notice. You can not worry about it "because it's not 2008" but it is causing extra wear. Whether hers will fail like a large number of Hyundai/Kia GDI engines I do not know. I personally don't care if it does or not because the engine is covered by the recall.

 

[Vuflanovsky]

Originally Posted by caprice_2nv
I'm sure they aren't all problematic but certain models under certain circumstances are. My girlfriend has a 2013 Hyundai Sonata with the 2.4gdi. She has followed the owners manual recommendations as far as adding a fuel system cleaner roughly every 15,000kms. It has 102,000kms now (62k miles) and has very noticeable pinging under light load. It's going to stay that way because she doesn't believe in over doing maintenance like I do on my ancient 83 and 84 cars. The vast majority of owners are like her, so the car is going to keep pinging and they won't even take notice. You can not worry about it "because it's not 2008" but it is causing extra wear. Whether hers will fail like a large number of Hyundai/Kia GDI engines I do not know. I personally don't care if it does or not because the engine is covered by the recall.


Just so you know, my post wasn't directed to you but a subset of people that will always be fearmongers to the extent that it doesn't represent the reality of everyday use for most people...in a technology that makes up 50% of new cars and somehow reflects early adoption since it's still 2007.

In your example, you might have to separate DI from the engine failure issue if the cause is connecting rods and not DI specifically...whether it pings or not. My naturally aspirated Gamma II DI car would occasionally ping on 87 octane but never on 89...so I use 89 octane gas. For others it's not that easy. The Gamma II ( a small DI engine ) is in the least recalled vehicle sold in America in MY2012-2017 that has among the highest reliability scores in its class. I think the point was not to not worry about DI where it's warranted to do so...but to look at DI for what it is in 2019 and not what it was....there's still a small group on here where that's a badge of honor.

I don't think I've ever seen actual or approximated percentages of the Theta II cars where engine failure occurred independent of the recall, so I can't make a call on how large the actual failure issue is versus owners who got the once over and a new dipstick and went on from there. Like has been posted here before...is it a 2% failure rate??...19% failure rate??....037% failure rate?? More importantly, how specific is the problem to DI versus design/manufacturing elements in those engines?? That's what I mean when some on here equate DI specifically to something it might not have anything to do with...

 

[caprice_2nv]

Originally Posted by Vuflanovsky
Originally Posted by caprice_2nv
I'm sure they aren't all problematic but certain models under certain circumstances are. My girlfriend has a 2013 Hyundai Sonata with the 2.4gdi. She has followed the owners manual recommendations as far as adding a fuel system cleaner roughly every 15,000kms. It has 102,000kms now (62k miles) and has very noticeable pinging under light load. It's going to stay that way because she doesn't believe in over doing maintenance like I do on my ancient 83 and 84 cars. The vast majority of owners are like her, so the car is going to keep pinging and they won't even take notice. You can not worry about it "because it's not 2008" but it is causing extra wear. Whether hers will fail like a large number of Hyundai/Kia GDI engines I do not know. I personally don't care if it does or not because the engine is covered by the recall.


Just so you know, my post wasn't directed to you but a subset of people that will always be fearmongers to the extent that it doesn't represent the reality of everyday use for most people...in a technology that makes up 50% of new cars and somehow reflects early adoption since it's still 2007.

In your example, you might have to separate DI from the engine failure issue if the cause is connecting rods and not DI specifically...whether it pings or not. My naturally aspirated Gamma II DI car would occasionally ping on 87 octane but never on 89...so I use 89 octane gas. For others it's not that easy. The Gamma II ( a small DI engine ) is in the least recalled vehicle sold in America in MY2012-2017 that has among the highest reliability scores in its class. I think the point was not to not worry about DI where it's warranted to do so...but to look at DI for what it is in 2019 and not what it was....there's still a small group on here where that's a badge of honor.

I don't think I've ever seen actual or approximated percentages of the Theta II cars where engine failure occurred independent of the recall, so I can't make a call on how large the actual failure issue is versus owners who got the once over and a new dipstick and went on from there. Like has been posted here before...is it a 2% failure rate??...19% failure rate??....037% failure rate?? More importantly, how specific is the problem to DI versus design/manufacturing elements in those engines?? That's what I mean when some on here equate DI specifically to something it might not have anything to do with...


My reply was mostly directed towards BMWturbodzl because I disagree that it's nothing to worry about at all. To be clear, I have no idea what the main cause of the theta 2 failures is...we know they are prone to oil consumption (which may have nothing to do with being direct injected). Fuel dilution is a problem with direct injection in some cases (like my girlfriend's short tripped car) yet hers doesn't seem to use oil. It just blackens the oil immediately after a change and smells like fuel. The issue is probably something to do with the design of the bottom end. As far as the percentage of failure I have seen 11% mentioned at least a couple times but not sure where that is coming from. Also the percentage will be constantly rising because there cars are just getting to the age where failures will be getting more common. They are not an older vehicle at all by my standards. Those are just quick thoughts off the top of my head while I'm running out the door at work.

 

[BMWTurboDzl]

Originally Posted by caprice_2nv
I'm sure they aren't all problematic but certain models under certain circumstances are. My girlfriend has a 2013 Hyundai Sonata with the 2.4gdi. She has followed the owners manual recommendations as far as adding a fuel system cleaner roughly every 15,000kms. It has 102,000kms now (62k miles) and has very noticeable pinging under light load. It's going to stay that way because she doesn't believe in over doing maintenance like I do on my ancient 83 and 84 cars. The vast majority of owners are like her, so the car is going to keep pinging and they won't even take notice. You can not worry about it "because it's not 2008" but it is causing extra wear. Whether hers will fail like a large number of Hyundai/Kia GDI engines I do not know. I personally don't care if it does or not because the engine is covered by the recall.



DI does have some characteristics such as fuel dilution (Honda Civics) and but I'm not so sure that it's an inherent problem with DI vs say a manufacturer using DI in combination with low tension rings in order to squeeze out more MPGS. In this case what technology do you blame? It is DI or the low tension rings? or maybe they use high tension rings and it's the boost levels because the manufacturer is trying to squeeze out more power so a DI 4-cylinder engine making 150hp might have less fuel dilution than a DI 4-cylinder engine making 255 hp. Basically some manufacturers have it figured out and some do not so I always hesitate to paint with a broad brush regarding automotive technology.

 

[StevieC]

Originally Posted by wemay
Member, StevieC used it on a Mini that was running rough and had illuminated its check engine light. After a treatment of the CRC GDi Cleaner, the light turned off the Mini ran better. If he reads this, maybe he can share more. Especially if I've misrepresented anything. I use it every 10k miles.


I've used it on a few direct injection vehicles both for maintenance and cylinder misfire related codes where it's valve gunk build-up related to direct injection. I really like the CRC cleaner for TGDI/GDI applications because it works and works well and IMO if it's used regularly you won't need valve cleaning where deposits are normally a problem.

Note: Not all GDI/TGDI have issues with valve deposits. Mazda is a good example.

 

[caprice_2nv]

Originally Posted by StevieC
Originally Posted by wemay
Member, StevieC used it on a Mini that was running rough and had illuminated its check engine light. After a treatment of the CRC GDi Cleaner, the light turned off the Mini ran better. If he reads this, maybe he can share more. Especially if I've misrepresented anything. I use it every 10k miles.


I've used it on a few direct injection vehicles both for maintenance and cylinder misfire related codes where it's valve gunk build-up related to direct injection. I really like the CRC cleaner for TGDI/GDI applications because it works and works well and IMO if it's used regularly you won't need valve cleaning where deposits are normally a problem.

Note: Not all GDI/TGDI have issues with valve deposits. Mazda is a good example.


I believe I read on here a long time ago about issues with the older direct injection (mazdaspeed engines I guess), but I've heard nothing bad about the newer stuff.

I will probably use CRC in my cars in the future. If it works on direct injection it should work on anything else. It's just that direct injection is more prone to buildup.

 

[Railrust]

I think the problems aren't as prevalent as people make them out to be, at least compared to earlier direct injection engines.

However when an engine ages and the mileage gets high, I can see worn piston rings adding more crank case pressure, and causing more blowbye to allow oil to escape into the PCV system and onto the back of the valves. At that point - with mileage probably being 200,000 plus - is it that much of an issue to remove the j take and clean the valves? I'd think if you're going the distance it shouldn't be.

I've had two direct injection cars so far. Oil changes - in my opinion - are important...the oil change interval. I find that with both my cars/trucks, the direct inject engine consumes more oil than in any of my previous port injection engines. Especially when I went with longer drains, then I'd really notice it (over 5,000 miles).

I did install an oil catch can on my 2018 Chevy Silverado...I don't have a problem draining it every couple thousand miles, and it seems to be catching a lot of stuff. I also try to add a cleaner to the intake when I do my oil change at 5,000 miles, right before I dump that oil. Does it help? I don't really know at this point, I haven't sent a scope down the throttle body and taken a look, but I will soon (probably when I reach 30,000 miles, I'm at 27,000).

I do like the power and fuel economy direct injection seems to bring, and knock on wood I haven't had any direct injection component failures yet (200,000 miles betweenness two cars....the other car was a Lexus LS460 that I traded in at 170,000 miles). That car had direct and port injec, but consumed oil like crazy towards the end.

 

[Cdn17Sport6MT]

Your Lexus, with dual injection, by virtue of the port injection (bathing the backs of the intake valves with semi-atomized gasoline - containing detergents) - would probably NOT have had any issues with carboning up the valves... Toyota / Lexus learned the hard way with the IS250 V6 (with low-tension piston rings and single- direct injection). That "cured" Toyota, from then on, re using single direct injection. Other credible mfr's, though, seem to be able to effectively run (solely) direct injection... with a fair amount of success...

The Mazda6 SkyActiv engines are (single) direct injected - and they seem to have a good track record. Similarly, Porsche? Likely others, too.

As for me, I think an effectively-engineered PCV flow filter system is worthwhile... Like a Mann-Hummel Provent 200, say. However, I think the hoses should be insulated well, and a minor, minor slipstream of engine coolant (heat tracing) should be run through, directly under the insulating covers. Also, pipe-sizes should be generous. The engine coolant heat tracing could be disabled when wintertime temps are high enough. I really have to worry about freezing-off the PCV flow... and then having the crankcase pressurize, blow out oil seals, etc... Much pain.

 

[caprice_2nv]

I think catch cans would be a big help on any of these engines as they get old and start to use some oil. The one I put on my old Caprice takes literally a couple minutes to empty.

 

[Railrust]

Originally Posted by Cdn17Sport6MT
Your Lexus, with dual injection, by virtue of the port injection (bathing the backs of the intake valves with semi-atomized gasoline - containing detergents) - would probably NOT have had any issues with carboning up the valves... Toyota / Lexus learned the hard way with the IS250 V6 (with low-tension piston rings and single- direct injection). That "cured" Toyota, from then on, re using single direct injection. Other credible mfr's, though, seem to be able to effectively run (solely) direct injection... with a fair amount of success...

The Mazda6 SkyActiv engines are (single) direct injected - and they seem to have a good track record. Similarly, Porsche? Likely others, too.

As for me, I think an effectively-engineered PCV flow filter system is worthwhile... Like a Mann-Hummel Provent 200, say. However, I think the hoses should be insulated well, and a minor, minor slipstream of engine coolant (heat tracing) should be run through, directly under the insulating covers. Also, pipe-sizes should be generous. The engine coolant heat tracing could be disabled when wintertime temps are high enough. I really have to worry about freezing-off the PCV flow... and then having the crankcase pressurize, blow out oil seals, etc... Much pain.


Yeah with the Lexus I didn't worry about carbon buildup on the valves, but oil consumption became a very real thing...and oil tracking into the intake.

As for the catch can in the winter, I never had an issue with the lines freezing...and I went through a two month stretch where temperatures were often below zero overnight, and driving to work that way (one hour commute). The contents in the can did freeze several times, but as for the lines? Didn't see anything. I think positioning of the lines is key - they must be positioned close enough to the engine to gather heat - and they must position in a way that pooling can't happen (a gathering of fluid). But for the most part it's only traces of oil and vapor in those lines heading up into that can, once it reaches the can, yes the contents will collect there and can freeze. So just empty it regularly so the can can't block flow. I never let mine go long enough where the level would raise that high. But as you know they can fill up pretty quickly in the winter due to condensation.

 

[caprice_2nv]

I don't know why, but mine appears to gather very little condensation considering the cold temps and my short 7 minute drive to and from work. I never noticed freezing but I only checked under the hood when the weather was warmer.

 

[Railrust]

Originally Posted by caprice_2nv
I think catch cans would be a big help on any of these engines as they get old and start to use some oil. The one I put on my old Caprice takes literally a couple minutes to empty.


I just can't see how it could hurt...yet people seem to be dead set against them. I understand if you are a "normal" person and don't ever want to open your hood and ever do a thing to your car (and I think that's why they don't come stock), but if you're handy and like working on a car? This is an easy thing to care for, just open the hood and drain the thing every few weeks...or buy one that drains into the crankcase on its own.

I was in a variable valve timing class a year ago...catch cans came up. My friend asked the instructor about them to kind of have a laugh at my expense (we do those types of things), but it back fired huge. The instructor went on for a half hour about how much he loved them, and then asked the class how many of them were running them...half the class raised their hands. These were top of the line techs, guys that own very successful shops in the area. A lot of them swear they are needed with direct inject. I'm an automotive instructor myself, I don't really see the harm in using them (as long as it's installed correctly and it's emptied regularly).

 

[Railrust]

Originally Posted by caprice_2nv
I don't know why, but mine appears to gather very little condensation considering the cold temps and my short 7 minute drive to and from work. I never noticed freezing but I only checked under the hood when the weather was warmer.


A couple reasons I can think of...

A well designed PCV system that actually separates some blow bye before it actually leaves the crankcase and allows it to drop right back into the engine.

You don't have a lot of blow bye

Or the can maybe doesn't have a very efficient baffle system that causes the vapors to condense?

But just looking at the picture, I would say there is some moisture mixed pretty well in that oil. So I'd say there is some condensation going on.

 

[caprice_2nv]

You're right, there is definitely moisture in the oil. It just doesn't look white and milkshaky like other pictures I've seen.

Also when I said a couple minutes to empty mine, that includes finding something to dispose of it. If I already had something it's literally like a 20 to 30 second thing. I empty it more frequently because it's not actually installed properly yet so it sits on a slight angle held in with zip ties. I empty it every few weeks and it seems to be about 10% full by then.