Direct injection carbon buildup problem

[RSXer]

Since both the 1.5T and 2.0L are DI, I assume they might eventually have carbon buildup?

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[Newflyer3]

Since both the 1.5T and 2.0L are DI, I assume they might eventually have carbon buildup?

I was reading the spec sheets on the Hondanews releases and it says that the 2.0L engine is port injected...

 

[RSXer]

I was reading the spec sheets on the Hondanews releases and it says that the 2.0L engine is port injected...

Oops you're right. But does anything about the 1.5T's specs tell us that it might not have the buildup issues?

 

[takemorepills]

No one has cracked that one yet. Even the new DI WRX is having gnarly buildup and requiring walnut blasting to a tune of $450+ a pop.
Only cars equipped with dual PFI/DI escape this issue. BRZ, FR-S, Toyota's newest DI V6, and the new NSX are a few to use 2 injectors per cylinder.
Gonna be interesting to see how this plays out for the Civic.

 

[Kane76]

No one has cracked that one yet. Even the new DI WRX is having gnarly buildup and requiring walnut blasting to a tune of $450+ a pop.
Only cars equipped with dual PFI/DI escape this issue. BRZ, FR-S, Toyota's newest DI V6, and the new NSX are a few to use 2 injectors per cylinder.
Gonna be interesting to see how this plays out for the Civic.

Maybe Honda managed to program the ECU to reduce carbon deposits. Theoretically it can be done by adjusting spark and valve timing.

We really won't know if this is going to be an issue with the 1.5T until owners rack up tens of thousands of miles.

 

[Tuttle]

Really not a huge deal. There's walnut blasting to clear carbon deposits if it ever becomes a problem. And even when it's a 'problem' it's really only a slight (imperceivable to most) drop in power.

 

[takemorepills]

So, I'd call having to "maintain" carbon buildup at $500-$700 a treatment a "big deal". The Subaru FA20DIT engines are getting buildup at around 15K miles that needs to be blasted.

We'll have to see if the new 1.5T, like every other DI engines, needs walnut blasting on a regular basis. If so, that takes away the "value" of owning a Civic.

Toyota deems carbon buildup such an issue that they are now implementing D4-S and D6-S on their DI engines, which is basically a full set, 4 or 6, port fuel injectors to wash the valves. I haven't seen anywhere that Honda is doing the same.

 

[Design]

Honda wouldn't have done direct injection of they hadn't solved the carbon buildup issue. I don't think they added secondary injectors to burn off deposits on the back side of the valves. So I suspect they used a combination of ECU timing and higher temps at the intake.

That said, it's impossible to eliminate some accumulation. I recommend using oil and fuel that are both high in detergents. Maybe an oil catch can. And perhaps use a DI cleaner through the TB. The key to using any chemical cleaner on direct injection is to ensure it atomizes while the engine is running at low RPM at operating temps.

My 2 cents...

 

[Design]

No one has cracked that one yet. Even the new DI WRX is having gnarly buildup and requiring walnut blasting to a tune of $450+ a pop.
Only cars equipped with dual PFI/DI escape this issue. BRZ, FR-S, Toyota's newest DI V6, and the new NSX are a few to use 2 injectors per cylinder.
Gonna be interesting to see how this plays out for the Civic.

I think Mazda and Ford have both gotten good results on their current designs. Ford tweaked the ECU timing and exhaust pulse on their Ecotech for smoother flow (earlier iterations suffered pretty bad as the intake valve was exposed to unburnt fuel). Mazda designed the Skyactive to maintain temps at the intake valves above 400*. Time will tell... but for now both setups have been reported to have minimal accumulation.

Edit: I should also mention that in both designs, the intake valve is completely sealed before fuel is sprayed into the cylinder. The only deposits occur through recirculation (EGR, PCV, etc).

 

[Fg4Marko]

Honda has introduced scavenging tech and new intake port design to combat this issue with carbon build up and has shown promise in reducing it significantly, there is a video somewhere on this topic about the engine. Im still sceptical now as i have no real data to show.

 

[G26okie]

Carbon build up on the mazdaspeed 2.3l turbo was pretty bad. Without an OCC, you were looking at pretty crazy build up by 60-80k. Of course, this engine was really the testing bed for the future ford ecoboosts, and was introduced nearly 10 years ago.

The pic below is at 10k miles.

 

[Shralper]

Honda wouldn't have done direct injection of they hadn't solved the carbon buildup issue.

Not necessarily true. Car manufacturers are going with DI turbos inspite of the carbon buildup problem for one reason- In order to meet Obama's draconian new CAFE/CO2 regs. They have no choice. All for a meager .5 MPG gain.

There is no real solution to the problem, aside from adding a second port injector per cylinder.

 

[xcoreflyup]

This engine will have carbon build up..I installed a mishimoto oil catch can. After 900 miles, the can is still empty but the baffle already has a layer of wet engine oil. My HB just past 4000 miles this week.

 

[Shralper]

This engine will have carbon build up..I installed a mishimoto oil catch can. After 900 miles, the can is still empty but the baffle already has a level of wet engine oil. My HB just past 4000 miles this week.

I'm just now getting very educated on this topic. A catch can only works if the oil vapors cool off long enough to condense; otherwise the oil vapors pass right through and back into the intake port.

Good article here, especially the comments section.

http://www.autoguide.com/auto-news/...a-problem-with-direct-injection-engines-.html

At this point I'll be seriously reading up a lot on removing the PCV hose, even though it will dirty up the engine bay. I don't want that crap being pumped back into my cylinders.

I REALLY wish I'd known this before buying an ST. I might trade it in for a V6 really soon, before they are all gone. Very few mfrs still offer them anymore thanks to Obama's new CAFE/CO2 regs. This is the last year Honda will offer the V6 Accord. Amazing how one man can destroy car engines without any real constitutional authority.

 

[kwaalude]

Amazing how one man can destroy car engines without any real constitutional authority.

Not sure the Founding Fathers had ICE and CAFE standards in mind when writing the constitution... but this isn't exactly a forum for political discourse

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