The problems with GDI

It's all about the additives that are added.
There's a BP at 15 Mile and a No Name station across the street. The No Name also states it gets the BP hauler to serve them. But what's inside that hauler's tank at No Name is a different, lesser additive blend.

Some vehicles get by on cheaper blends. Others need more. Some vehicles show rough idles at 20k - some don't using the same exact gas. Do a 20k experiment at each. That will give you a better answer to their ratings, as seen fit by your specific vehicle.
Sure, but when are they added? At the gas station? Who adds them? The truck driver?
 
Sounds a bit hard to believe.
In the fuel section of BITOG there was a long thread started by a fuel tanker driver. You can search for it if you want. The additives are blended in at the terminal when the tanker takes their load. Those tankers deliver to many different gas stations but doesn't mean they have the same additive in each delivery, only thing in common is it's the same tanker hauler company.

EDIT: Found the post.. here you go

"The only thing that makes gasoline brands different is when it is loaded on the truck. All base gasoline that comes out of the refinery and into the pipeline is the same. The additive package that is injected during the loaded process is what makes Amoco, Amoco or Shell, Shell, or BP, BP, etc etc."
 
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... I installed a catch can, on one side of the engine, driver side is i remember correctly, with a top of the line Mishimoto catch can, inline of the PCV system. After 3000 or so miles, it was nearly full, as witness by the sight tube on the side. ...
Thanks, this is the kind of pragmatic evidence-based reply that I am looking for. The maintenance manual for my Mazda3 doesn't mention the air/oil separator, and it's not easy to access, so I'll definitely take a look at it when I flush the coolant, and drain or clean it out if necessary. I'll try to remember to take photos and post them here.

My Mazda3 doesn't have a lot of miles (57k in 11 years) but gets driven at least weekly, on the freeway, and revved out the way it should be (manually tranny). That should be ideal to minimize deposits. We'll see.
 
I would have hoped by now the GDI issues would be ancient history, IMO they still don't have it right. Maybe now that ICE engines aren't going to be forced out of existence as quickly as I thought a few months ago, hopefully now mfgs. will work a little harder to improve them. Flame suit on.
 
Those tankers deliver to many different gas stations but doesn't mean they have the same additive in each delivery, only thing in common is it's the same tanker hauler company
One tanker would be common between several different stations, plus residual from the load before. Point being. Who does not have top tier fuel?
The additives are blended in at the terminal when the tanker takes their load.
This is more believable.
 
One tanker would be common between several different stations, plus residual from the load before. Point being. Who does not have top tier fuel?


This is more believable.
right, separate compartments on the tanker.. was mentioned in that thread I linked to from the fuel section on BITOG.

and I think Top Tier is the level of additives they put in the fuel, some brands join to agree to that level.
 
It is interesting that the Civic has gone back to port injection for the 2.0l and it has higher compression than their 1.5T, and the same combined mileage ratings.... The turbo has more torque and hp, but if you don't care, then the more complex engine has really done nothing for you?
Interesting comment - makes me wonder if there may be more improvements coming in port injection systems for future engines allowing a move back from GDI ? I own both GDI and PFI engines in my family and I prefer PFI engines in part due to longer possible OCI’s and ease / lower cost of keeping engines clean.
 
Interesting comment - makes me wonder if there may be more improvements coming in port injection systems for future engines allowing a move back from GDI ? I own both GDI and PFI engines in my family and I prefer PFI engines in part due to longer possible OCI’s and ease / lower cost of keeping engines clean.
Anything is possible, and one can only hope.
 
Interesting comment - makes me wonder if there may be more improvements coming in port injection systems for future engines allowing a move back from GDI ? I own both GDI and PFI engines in my family and I prefer PFI engines in part due to longer possible OCI’s and ease / lower cost of keeping engines clean.
I think it's been mentioned in one of the early pages of the thread, but some makers, notably Toyota, are combining both. Their name for it is D4S. These cars have BOTH direct and port injection. The ECU determines at any given moment which system to use, and often combines the two at the same time. One of the benefits, allegedly, is the reduction of carbon buildup, though I've seen some pics indicating that buildup still happens to some extent. Both our vehicles have D4S, though it's too early in their lives for me to offer any meaningful observations (my wife's '23 only just hit 10k miles). One notable side effect: if you're aware (as I usually am...), you can hear the difference in modes. On the Camry, the engine cover is nothing but a big chunk of very dense, black foam rubber -- oil drips soak into it like a sponge and can't be wiped off (grrr). I'm surmising the stuff is meant to absorb the sound of the direct injectors. Obviously, owning two examples now, I'm hoping that D4S actually does, in the long run, offer the best of both systems, especially minimal carbon deposition.
 
The long oci people are going to have a hard time with this info. I remember when 10k oci's were fought tooth and nail on here. Now you are wasting oil if changing before 10k+. Is the pendulum swing the other way again??
Oil change intervals depend on engine design, operation and oil type used.
 
There was a lot of talk that those that are operated in a race type setting don't have that issue. When I had the top taken off of mine to replace the injectors recently the master technician seem to think that my maintenance regiment was helping but he did also comment that having the high flow intake system while it would not add a lot of power without a proper tune, that because it was getting air in faster at a higher velocity it could help to some degree with deposits as it passes through faster. The idea that it gets on the highway every day and gets hot which in his opinion is around 20 minutes after it reaches operating temperature. I have tried to keep up on using the gum out multi-tune or a brand name engine oil flush as I think it helps keep the Rings cleaner and helps remove any carbon or build up that may be left swimming around in the engine.
 
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