Oil, Carbon build up palooza!

[Chris_Top_Her]

One anecdotal example of carbon build up does not represent a systemic problem throughout the Skyactiv lineup. This is the only example of buildup I've seen, if this was a widespread problem I'm inclined to believe we would have seen more incidents over the years.

It's a feature systemic to ALL di engines.. the degree depends on so many factors and in the end the objective is to maintain maximum performance from cleaner fuel charge and reducing accumulatipn of deposit on the valve. I've seen it on both sky engines I've had. If ao had the diesel I'd install one for sure that engine has all sorts of dilution issues.
Nothing cosmic about an oil catch can. They work and they are a better albeit more involved solution that the oil seperators standard on di engines.. the problem with oem seps is that they recirc the junk back into the intake. Ideally it would be stored for drainage but that means an extra maintenece item.

Here is a good breakdown of what they do. Also if you have other automotive inquiries on technical subjects check his channel out.

 

[Chris_Top_Her]

Did you take the bumper off? If not how did manage to reach the bottom bolt on the manifold?

 

[Chris_Top_Her]

how felix? little instructions would help TIA

Valve cleaner and a toothbrush and towel. You'll wanna start with the valves that are closed so you can clean them without putting the garbage into the chamber. Then move the crankshaft clockwise (direction of rotation) and do whichever ones werent closed. If you are trying to walnut blast or something you defintely have to make sure the valve is closed, if you are just using cleaners it's not as vital but you don't want a bunch of carbon bits in the chamber. Also a bunch of videos on youtube "direct injection valve cleaning"

I.e

 

[Driver 1]

Did you take the bumper off? If not how did manage to reach the bottom bolt on the manifold?

Just blindly feel the bolt. 1/4 rachet would do

 

[Driver 1]

question, can I use the throttle body cleaner to clean the intake valves?

 

[Chris_Top_Her]

question, can I use the throttle body cleaner to clean the intake valves?

I wouldn't spray it into the intake while running but I don't see why it wouldn't be fine for manual cleaning.

 

[Chris_Top_Her]

I got about 50-75ml when I changed my oil plus some that spilled out when I took the cap off the hose. That's after about 7ooo miles which is the longest interval I've done this far. It's also the least amount of catch I've drained since I've had the can. I drained out 5w30. The previous times I've changed my oil was usually around 5k, with oem ow20 moly and it produced way more catch and also the oil was always pitch black compared to the 5w30 I used for a longer period. Seems like the 5w30 is better at reducing blowby however this time I added 0w20 (not oem).

 

[Driver 1]

I wouldn't spray it into the intake while running but I don't see why it wouldn't be fine for manual cleaning.

WD 40 throttle body cleaner's instruction says to spray while engine is running but there's also a fine print that says it's optimal to remove the throttle body when cleaning.

So can I use it while engine is running? I don't want to remove the manifold again and turn the crank to open/ close the valves manually just too much work, I'm lazy haha

Saw a intake valve cleaner by CRC, instructions are very simple I dunno if it's effective though.

I got about 50-75ml when I changed my oil plus some that spilled out when I took the cap off the hose. That's after about 7ooo miles which is the longest interval I've done this far. It's also the least amount of catch I've drained since I've had the can. I drained out 5w30. The previous times I've changed my oil was usually around 5k, with oem ow20 moly and it produced way more catch and also the oil was always pitch black compared to the 5w30 I used for a longer period. Seems like the 5w30 is better at reducing blowby however this time I added 0w20 (not oem).

nice soup you got there Chris! yummy!

 

[yrwei52]

One anecdotal example of carbon build up does not represent a systemic problem throughout the Skyactiv lineup. This is the only example of buildup I've seen, if this was a widespread problem I'm inclined to believe we would have seen more incidents over the years.

Actually this's not just one single example. I saw Christ_Top_Her's post a while ago stating the carbon build-up issue when he took the intake manifold out. That's why he installed the catch can. Most CX-5 owner's don't take intake manifold out and they can't see the carbon build-up. But whoever here who took it out and he'd see the issue.

 

[erhayes]

I think I will wait and see if the performance is being compromised before I start unbolting the intake manifold. ed

 

[yrwei52]

I got about 50-75ml when I changed my oil plus some that spilled out when I took the cap off the hose. That's after about 7ooo miles which is the longest interval I've done this far. It's also the least amount of catch I've drained since I've had the can. I drained out 5w30. The previous times I've changed my oil was usually around 5k, with oem ow20 moly and it produced way more catch and also the oil was always pitch black compared to the 5w30 I used for a longer period. Seems like the 5w30 is better at reducing blowby however this time I added 0w20 (not oem).

Yep last time your picture did show way more stuff from your catch can. So looks like GJ-Molestor does have a point urging us to use at least 5W-30 as specified in the owner's manual for other regions.

My CX-5 is the first vehicle using watery 0W-20 oil, and again like GJ-Molestor had said, I also feel the engine and valve clapping noise is higher than my other much older vehicles during idle which I don't like. I may try 5W-30 oil instead of 0W-20 Mazda Moly next time to see the difference.

 

[Puyapim]

I would definitely stick with d1G2 oils or the SN+ which is coming out now. The grade would be a personal choice.

 

[Chris_Top_Her]

WD 40 throttle body cleaner's instruction says to spray while engine is running but there's also a fine print that says it's optimal to remove the throttle body when cleaning.

So can I use it while engine is running? I don't want to remove the manifold again and turn the crank to open/ close the valves manually just too much work, I'm lazy haha

Saw a intake valve cleaner by CRC, instructions are very simple I dunno if it's effective though.



nice soup you got there Chris! yummy!

If it says it can be used as such then take off the pcv hpse on the intake and spray it through there while its running per instruction as long as its past the maf

 

[Chris_Top_Her]

March 2016. I had one posted before from a different change that was more but I think I linked it from a FB post I made and can't find it. ow20 ~5000mi

 

[Lbear]

No doubt that direct injection causes more carbon buildup on valves and intake. This is noted in almost every long term car study engine teardown.

Only options are running Tier 1 gasoline, which helps. Revving it and running it hard every so often to "clean" the carbon out.

Some claim higher (91+) octane can help. Keeping idle times down. Avoiding short engine runs (under 10 miles), as the engine never gets a chance to fully warm up.

 

[Kedis82ZE8]

Aren't some manufacturers now selling a hybrid with both port and direct injection?

Does a Seafoam treatment on the intake of a direct injected motor work?

 

[RepeatMazda]

Aren't some manufacturers now selling a hybrid with both port and direct injection?

Does a Seafoam treatment on the intake of a direct injected motor work?

Yes, some manufacturers are doing that.

In theory, an intake treatment done through the intake/throttle body could remove some of the deposits. The issue with this method is that getting an even disbursement of the chemical is extremely difficult to achieve. Pooling is more than likely going to occur, so how much even cleaning is really being achieved? I do know that Gumout is testing various delivery methods to solve this problem. With that being said, I wouldn't use Seafoam specifically. It's overpriced for what it is. I won't advocate for any particular product, but do a little research on the various treatment options and pick the one with chemical profile you like best.

 

[Puyapim]

Over on BITOG there was a recent thread on fuel additives. In particular one poster suggested using Redline S1 in maintenance amounts to prevent issues rather than waiting until the problem presents itself. Informative discussion.

https://www.bobistheoilguy.com/foru...cs/4697626/all/Do_You_use_a_fuel_additive_?_W

 

[clownshoes2]

Wouldn't a complete tank of 91 or 94 octane with a good amount of fuel system cleaner and a good long run (2+ hours) on the highway take care of some of the carbon build up?

 

[finch204]

Wouldn't a complete tank of 91 or 94 octane with a good amount of fuel system cleaner and a good long run (2+ hours) on the highway take care of some of the carbon build up?

Not really because fuel is injected in a direct injection engine. So you do not get the benefit of cleaning the intake valves like in a port injection engine. The fuel system cleaner will only be cleaning your fuel lines and possibly the fuel injectors, but won't do anything for the buildup on the valves.