Why DIrect Injection is really bad!

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Originally Posted By: tig1
What about the $1500 fuel pump for DI? Any truth to it?


FWIW: The HPFP (High Pressure Fuel Pump) that is mechanically driven off the camshaft on the Kia/Hyundai GDI engines is typically ~$400.
 
Originally Posted By: demarpaint
Originally Posted By: 2015_PSD
Originally Posted By: rotorcraft230
Looks like to me that 4 ports are cracked between the valves on the head.
Agreed; those are not casting lines. Not sure what it means for that engine, but it is particularly obvious on this photo:

Interesting, I'd love to see that.

Those are casting lines.

Honestly, the stuff I see on here sometimes...
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For the mileage, not sure I see anything too out of the ordinary. Honestly, I've seen port injected engines look worse...

Sure is a lot of fear of anything new in technology on this board. As was mentioned, DI isn't exactly "new" anymore - been around for many years now!
 
My DI engine hygiene : Top Tier Fuel , Low Calcium Dexos approved synthetic oil (M1) , < than 5,000 mile OCI's , don't lug the engine , every three months take it out on the interstate for a : "Italian Tune up" (20 minutes at 4,000 RMPM's ) , walnut shell blast by Hyundai before 100K miles.
 
Bunch of nonsense. If someone decides to spend hours cleaning up stains that have absolutely no impact on engine performance, then they should seek help for their OCD. Also, most PFI engine with that many miles and EGR running through the intake will have a similar looking intake tract.
Sure, some engine will have intake deposits bad enough to affect performance, but for the most part that's not the case.
 
I also do italian tune up variations, but mainly to ensure that the high PEA I add has a way to push high volumes through the injectors. The tune up won't do much for the back of those valves unless the engine has one of those faboed timing set ups that gets fuel behind the valves (one theory that explained ecoboost dilution and high fuel use with ability to go 100k wuth no cleaning). I understand that changing too often keeps the noack elevated and makes the oil problem in the system worse. I vaguely remember that being a reason to not change the BMW oil too frequently as per some BMW recommendation...

I am currently investigating walnut blasting options along with an atf flush for Xmas. Well, ok maybe methanol injection for Xmas but the basics need to be done first.


Originally Posted By: ChrisD46
My DI engine hygiene : Top Tier Fuel , Low Calcium Dexos approved synthetic oil (M1) , < than 5,000 mile OCI's , don't lug the engine , every three months take it out on the interstate for a : "Italian Tune up" (20 minutes at 4,000 RMPM's ) , walnut shell blast by Hyundai before 100K miles.
 
Intake track and valve deposits are one of the reasons Ford designed the 2017 Ecoboost with a dual fuel system DI, and port injection.

"really bad" I wouldnt agree as it deliver gains with said compromise in intake track deposits on a single fuel delivery system.



UD
 
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I have a 2008 Cadillac with a DI 3.6 engine and it's never given me any problems. Good performance and fuel mileage for 130,000 miles. I wouldn't hesitate to buy another DI engine.
 
Originally Posted By: UncleDave
Intake track and valve deposits are one of the reasons Ford designed the 2017 Ecoboost with a dual fuel system DI, and port injection.

"really bad" I wouldnt agree as it deliver gains with said compromise in intake track deposits on a single fuel delivery system.



UD


I have a feeling Ford might have really nailed it with this design change. I bet in a year or two the system will be as good as it gets for them. It will be interesting for me to follow.
 
To me, these photographs are a clear sign of the fully vapourised light front-end of your engine oil routing itself through the PCV system, into the intake system and onto be burnt. The deposits you're seeing in the photos probably represent a small fraction of the oil that has passed through the system.

Whilst I agree that condensed deposits in the intake won't make that a big difference to the operation of your engine, the oil that reached the engine could make a big difference. You're risking sticking an oil control ring which you will only know about when your oil consumption skyrockets. You're also risking your piston crowns running hotter than they should do (deposits in the first groove will reduce the rate of heat transfer from the piston, through the compression ring, to the cylinder wall. Finally, as this is a GDI engine, all those deposits in the cylinder are going to push you to a situation where both conventional knock and LSPI are more likely.

Do your engine a favour and run it on the lowest Noack oil you can lay your hands on...
 
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Just an FYI, that Honda engine is showing signs of oil contamination from the PCV valve. It has nothing to do with the EGR system. That actually looks pretty clean. The black "soot" is from the EGR system. Honda used to use pre cat exhaust for the EGR, now they use post cat exhaust, causes less build up in the EGR system. But again, that is FAR from having an EGR soot problem.

How much oil does it burn? We see this a lot with people that use just a dino 5W20 and only follow the OLM.

I am having trouble what the original post is trying to prove/disprove here?
 
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