Direct Injection Only

[Al]

Both m y 2018 Forester XT and '22 Forester have DI. All subaru carlines started DI only in their unturboed vehicals (FB) in 2019. Tha FA mostly turboed has been Di for like a decade I believe. I have been doing the CRC intake and turbo cleaner every 7,500 miles. CRC recommends every 10,000 miles. The process takes 20 minutes it consists of about 250 individual sprays. The before and after pictures on Youtube are shown where the buildup has reached overload on buildup. The "after" pics are much improved but not great. 50% of terrible is still terrible.

CRC claims "up to 46 percent removal". After the 1 hour heat soak a lot of smoke comes out the tailpipe. I hope it is coming from the carbon on the valves but who knows. I was planning on walnut blasting my '18XT at 50,000 miles, but that is about the time my extended warranty runs out. My '22 has 13,000 on it. I may not have it long enough to see if there is buildup.

Obviously this DI only is being used bc it delivers increased performance and efficiency. I am guessing more DI + Port injection will be used going forward. MY '22 Forester does get 33 mpg+ on the highway and 26 around town. Pretty good for a vehicle with fuyll-time AWD and aerodynamics of a brick.

 

[buster]

I'm surprised we haven't seen more DI and Port by now. Have you been able to see how much buildup there actually is?

 

[Al]

No I have not. I will see if I can get my attachment down there.

 

[jurko]

My golf is also only DI and at almost 71K miles I sometimes wonder what the IV's look like.
So far I don't feel any sort of loos of power and idle is buttery smooth without any hiccups but who knows.
Aren't the VW's sold in Europe with dual DI/Port injection but not in US and Canada?
If that's true I wonder why that is.

 

[buster]

The PCV innovations are GM's method of tackling DI problems, just as Ford and Toyota embrace dual injection.

https://gmauthority.com/blog/2019/01/gm-patents-innovative-new-integrated-oil-separator-assembly/

 

[UG_Passat]

Toyota/Lexus has been doing dual injection for over 15 years already.

 

[jurko]

The PCV innovations are GM's method of tackling DI problems, just as Ford and Toyota embrace dual injection.

https://gmauthority.com/blog/2019/01/gm-patents-innovative-new-integrated-oil-separator-assembly/

Thanks for the link.

 

[DemoFly]

My golf is also only DI and at almost 71K miles I sometimes wonder what the IV's look like.
So far I don't feel any sort of loos of power and idle is buttery smooth without any hiccups but who knows.
Aren't the VW's sold in Europe with dual DI/Port injection but not in US and Canada?
If that's true I wonder why that is.

Our cars are twins and at 48k my intake valves were pretty bad. A local euro shop cleaned them for $140. Truth be told, not a difficult DIY, but they had the walnut blasting machine and I said what the heck.

 

[jurko]

Our cars are twins and at 48k my intake valves were pretty bad. A local euro shop cleaned them for $140. Truth be told, not a difficult DIY, but they had the walnut blasting machine and I said what the heck.

Now you got me thinking. $140? That sounds like a great deal. I will look into it.

 

[jurko]

Our cars are twins and at 48k my intake valves were pretty bad. A local euro shop cleaned them for $140. Truth be told, not a difficult DIY, but they had the walnut blasting machine and I said what the heck.

Nice looking Golf. Looks like you upgraded the wheels. Any other mods you've done to it?
I got German Rials wheels, Spoolen Dog Bone and lowered the car with VWR springs.
The picture is before springs change.

 

[Greasymechtech]

Its getting very noticeably when I go 10k miles without the IV spraying. So, have now adopted a more frequent interval with both of the GDI-only headaches in the driveway.

CRC is just one of many. Don't get hung up on brand loyalty.

I run the gauntlet... for example:

Deep Clean GDI – Lucas Oil Products, Inc. – Keep That Engine Alive!

lucasoil.com

Pro-Series Intake Valve Cleaner | STP®

STP® Pro-Series Intake Valve Cleaner is a DIY intake valve cleaning solution designed to remove hardened deposits without a costly engine teardown.

www.stp.com

https://www.amsoil.com/p/power-foam-apf/

Sea Foam Spray | Intake Valve and Top Engine Cleaner and Lubricant

Sea Foam Spray Top Engine Cleaner & Lube works through an engine’s upper intake to clean harmful deposits from intake valves and chamber areas.

seafoamworks.com

Berryman® Intake Valve & Combustion Chamber Cleaner

www.berrymanproducts.com

Optimizer™

MOC® Optimizer™ (#16501) is a unique foaming aerosol cleaner designed to remove carbon and other deposits in the fuel induction system

mocproducts.com

ATP AT-100 Intake Blast Intake System Cleaner

Easy to use, aerosol charged solution for top end engine cleaning ATP AT-100 Intake Blast offers the latest technology in top end engine cleaning. This easy to use, aerosol charged solution applies a highly concentrated cleaning solvent through the plenum

atpautomotive.com

Pro-Line Throttle Valve Cleaner

A mixture of cleaning agents for cleaning and maintaining intake manifold and throttle body of Gasoline engines. Dissolves and removes deposits and contaminants, restores normal function of moving parts. Also ideally suited to clean intake valves of modern GDI engines. Regular use keeps the...

www.liqui-moly.com

Some of the other ones, like Lubegard, RoyalPurple, Regane... have sold out or just disappeared. Others requires professional tools since they come in liquid only and need an air compressor, a product can dispenser, and a misting nozzle/hose.

Water mist can also be used. I'd say that some of us get a mild cleaning driving thru every downpour or trip thru the car wash. Annoys wife when I hold RPM at 2000rpm in neutral throughout the automatic car wash.

New BMW M water injection system

The BMW M4 GTS is the first series-produced street vehicle to utilise an innovative and pioneering water injection system that further optimises the performance and consumption of the turbocharged six-cylinder inline engine, even at full performance capacity.

www.bmw-m.com

Since we already know that condensation/catch cans aren't a solution, I doubt that GM's dual separator will do much for IV deposits. Hoping that the higher PSI GDI helps with less crud and stress on the oil. I believe the Koreans went 250bar on their newer engines and Nissan has the 350bar on a few too.

GDi: The future of the internal combustion engine | Delphi Auto Parts

In December 2018, the European Union agreed on new regulations to reduce CO2 emissions from cars by 2025 and 2030.

www.delphiautoparts.com

500+ Bar GDi System - BorgWarner

BorgWarner cuts particulate emissions, improves fuel economy with an industry-leading solution for 500+ bar gasoline direct injection systems.

www.borgwarner.com

 

[benjy]

never heard of $140 for a walnut blasting!!! prolly NOT!! both injections are of course costlier + manufactures have been moot since DI came out + as more quietly switch to both to NOT alarm perspective buyers!!!! NO solo DI EVER for me!!! + CVT's also in that NEVER!!! lots of products that MAY help a bit while lightening your $$$$

 

[DemoFly]

Nice looking Golf. Looks like you upgraded the wheels. Any other mods you've done to it?
I got German Rials wheels, Spoolen Dog Bone and lowered the car with VWR springs.
The picture is before springs change.
View attachment 122479

All stock except for the wheels and weathertech rain guards. I bought it like this in May.

 

[zzyzzx]

If you are going to guy a Subaru anyway, what incentive do they have to fix the problem?

 

[SC Maintenance]

DI+PI likely isn't perfect either - maybe prolongs the carbon buildup past what most original owners keep the car. Also these new cars are running a lot more atkinson cycle than they used to - which likely doesn't cause the problem but likely makes it worse - the cost of better mileage.

The additional benefit of DI+PI is that you run PI+DI both at the top end / WOT - so you can size your DI injectors a little smaller which supposedly makes them a little more efficient.

Of course 2 sets of injectors cost more money and leaves twice as many parts to fail. No perfect world.

I have read on lots of boards where some people have tons of problems with DI and some don't - might have something to do with driving patterns.

Lots of people claim a catch can helps. I wonder if the oil type helps - technically SP is supposed to help with DI carbon in general, but I wonder how brands compare?

 

[BMWTurboDzl]

Aren't the VW's sold in Europe with dual DI/Port injection but not in US and Canada?
If that's true I wonder why that is.

It part it's because of $$$. Customers are very price sensitive in some segments especially where VW operates.

 

[Cujet]

The complexity of my Ford 2.7L EB dual injector setup is impressive. Got to admit, it works rather well though. The hope is that with each injector working half as much, they will not wear out or stick quite as rapidly.

 

[WobblyElvis]

Myself and immediate family have put maybe 250,000 miles on DI engines without any cleaning what so ever. No sign of any problem. I believe the intake valve deposit problem is over hyped to scare people into buying borderline useless products. Of course, there are some very rare exceptions. Should I see first hand, an IV deposit problem cleared up by a spray can, perhaps I'll change my mind.

 

[DemoFly]

Just because you've never had an issue doesn't mean there isn't tons of evidence online from other people. The biggest issues are high pressure fuel pumps being unreliable, the complex injectors themselves being unreliable and killing the engine, carbon deposits breaking off the valve and cracking the valve in interference engines, and things as simple as misfiring due to bad valve seat seal.

 

[zzyzzx]

Myself and immediate family have put maybe 250,000 miles on DI engines without any cleaning what so ever. No sign of any problem. I believe the intake valve deposit problem is over hyped to scare people into buying borderline useless products. Of course, there are some very rare exceptions. Should I see first hand, an IV deposit problem cleared up by a spray can, perhaps I'll change my mind.

Try putting that 250,000 miles on one car, and make it not a Ford or Toyota and report back.