Direct injection carbon buildup on intake valves could be thing of the past

50,000 on mine and it is still the same. Maybe I'll take out the gtech at some point and retest to see if it's still 7.5 seconds to 60.

Okay thanks.

From what I gather, heat is a skyactiv engine's best friend :)
 
Okay thanks.

From what I gather, heat is a skyactiv engine's best friend :)

More accurately, heat control.

Yes, intake valves are designed to retain heat, combustion chamber is designed to shed heat, etc. It's all about making sure the engine runs optimally in all conditions.

Based on the lack of issues with the Skyactiv G engines, it looks like Mazda hit a home run.
 
Are you saying the 2.5L G has issues I haven't heard about?

I'm aware of the issues with the diesels.

Not speaking for Paris, but the "G" was highlighted in read. The "D" suffix is the only other one as relates to the SA engine series, thus logically given "one out of two" that he means the diesel.
 
And the D doesn't really have issues, it's just that people want a Diesel to be short-trip friendly and they're just not made for commuting short distances.
 
D has issue (as described, yes that's an issue not shared by G), and so do other DPFequipped diesels.
 
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Not speaking for Paris, but the "G" was highlighted in read. The "D" suffix is the only other one as relates to the SA engine series, thus logically given "one out of two" that he means the diesel.
I would have thought this was pretty obvious MikeM!
 
And the D doesn't really have issues, it's just that people want a Diesel to be short-trip friendly and they're just not made for commuting short distances.
Tell that to all those UK owners whose engines are failing right and left. And BTW, if European diesel auto sales constitute 50% of the total mix, how many of those owners do you think scrupulously avoid making too many short trips?
 
Tell that to all those UK owners whose engines are failing right and left. And BTW, if European diesel auto sales constitute 50% of the total mix, how many of those owners do you think scrupulously avoid making too many short trips?

The issues didn't crop up until recent emission standards kicked in causing things to get overly complicated. I'm all for a cleaner environment but it's going to be hard for automakers to meet goals if the use-case for the vehicles don't match consumer expectation.
 
The issues didn't crop up until recent emission standards kicked in causing things to get overly complicated. I'm all for a cleaner environment but it's going to be hard for automakers to meet goals if the use-case for the vehicles don't match consumer expectation.



Yes, clean diesels are expensive and complicated. Clean gasoline engines are less so. Europe's reliance on diesels in small passenger cars has a price. I do not expect significant diesel passenger car growth in U.S. Americans tend to be reluctant to pay the big price premium for the diesel car itself, not to mention the higher cost per gallon for diesel fuel.

The stink and particulate filth (and health impact) of older diesels won't be missed. The curbs / kerbs are black unfortunately for a reason.
 
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I am just wondering about the PCV system. Will serving this system help to keep these valves clean? On my old car it was right on top of the valve cover. This one is hidden. From what I've read its under the intake manifold. Can I get to it by removing the cover under the engine bay, and go from underneath? Or do I have to remove the intake? As far as intakes go, it looks pretty easy to remove, but would rather not if I dont have to.
I am not sure but it looks like its kind of already has a catch can built into the system. But if anyone can elaborate on that please do? So I am coming up on 50,000 miles. So my next maintenance will include new mazda plugs, drain and fill of the manual transmission. Should I look into the PCV system. The replacement cost of these parts are very reasonable.
 

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TimberSTX you have it figured out. The PCV does rest inside an oil catch separator built into the engine. Oil is allowed to drain back down through to the engine sump, and the only thing that vents to the intake are fumes. That said, running a low NOACK volatility oil like Mobil 1 will reduce off-gassing and further carbon build up on your valves in theory. I got upset with Pennzoil when they increased their NOACK from 8 to 12.9 on their newer synthetics.
 
ours has some signs of carbon buildup with 50k miles on the odometer.

if you do not rev the car hard at least once a month and do regular highway driving the buildup will occur.
 
ours has some signs of carbon buildup with 50k miles on the odometer.

if you do not rev the car hard at least once a month and do regular highway driving the buildup will occur.

Should probably update the thread with the news that your "signs of carbon buildup" went away with an oil change during which you way overfilled the engine. (hand)
 
Should probably update the thread with the news that your "signs of carbon buildup" went away with an oil change during which you way overfilled the engine. (hand)

Lol.

The sound was present with the oil level perfectly normal and not overfilled! I added an extra quart because the dipstick gave me an inaccurate reading and that made no difference.
 
The issues didn't crop up until recent emission standards kicked in causing things to get overly complicated. I'm all for a cleaner environment but it's going to be hard for automakers to meet goals if the use-case for the vehicles don't match consumer expectation.

...but now we have cleaner vehicles that ALSO meet expectation...teething issues happen, but evolution occurs and a better mousetrap is made. Remember how EFI was the devil? Then DI was the devil.
 
By now we have many CX-5 owners w/Skyactiv engines at over 30K miles. Any issues related to CEL / carbon build up?

read over the thread if youre interested. These new engines do not have carbon buildup.

Bump thread.

Anyone with 30k plus miles report any effects due to DI carbon buildup?

MY 2007 DI CX7 was running like new when I sold it at ~ 80,000 miles and now Mazda claims they have solved the issue with later engines. Ed

Correct

Anything new here?

No. This has been resolved. No buildup issues.
 
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