INTAKE valve crud

erhayes

Contributor
:
2022CX5 PP
MAZDA has attacked the DI problem by, keeping the intake valve temperature up. It appears that ir is a step in the right direction but, not completely successful based on BITOG responses. Has Mazda made any improvements in the 2019 engines to alleviate the problem entirely? Ed
 
Can be addressed with a head cleaner through the vacuum system. Also good for the Pcv system to help keep valve from getting stuck. If you are the don't do anything until there is a problem type a manual cleaning might be required
 
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MAZDA has attacked the DI problem by, keeping the intake valve temperature up. It appears that ir is a step in the right direction but, not completely successful based on BITOG responses. Has Mazda made any improvements in the 2019 engines to alleviate the problem entirely? Ed
No.

Like Kedis82ZE8 said, Toyota's new 203~206hp Dynamic Force 2.5L does implement both direct and port fuel injection systems which should help to minimize such issue.
 
Can be addressed with a head cleaner through the vacuum system. Also good for the Pcv system to help keep valve from getting stuck. If you are the don't do anything until there is a problem type a manual cleaning might be required
Still waiting for promised picture of vacuum hose where we can spray some head cleaner into the valve area ⋯ ;)
 
Awkward video. Blow-by described backward from what really happens. I quit watching.

How about a pic of a Sky-Active Port/valve at 30k miles?
 
may be wrong but the lack of many videos with cx5,cx9 for valve carbon issues vs so many videos for ford, bmw, etc....may either mean its not that big of a deal for newer mazdas or mazda just did not sold that many as ford,bmw. etc...which is also true. time will tell when we get many high milers in the next few years to come.
Highest miles cx5 I have read/found on the net is nearing 200k miles no issues from that perspective.
 
Awkward video. Blow-by described backward from what really happens. I quit watching.

How about a pic of a Sky-Active Port/valve at 30k miles?
may be wrong but the lack of many videos with cx5,cx9 for valve carbon issues vs so many videos for ford, bmw, etc....may either mean its not that big of a deal for newer mazdas or mazda just did not sold that many as ford,bmw. etc...which is also true. time will tell when we get many high milers in the next few years to come.
Highest miles cx5 I have read/found on the net is nearing 200k miles no issues from that perspective.
You can see a couple of videos in this thread posted by felixd. His CX-5 has only 18K miles (28.9xx kms) but the condition on intake valve deposit looks bad!

Video Cleaning Intake valves CX 5 Skyactiv Gasoline engine
 
may be wrong but the lack of many videos with cx5,cx9 for valve carbon issues vs so many videos for ford, bmw, etc....may either mean its not that big of a deal for newer mazdas or mazda just did not sold that many as ford,bmw. etc...which is also true. time will tell when we get many high milers in the next few years to come.
Highest miles cx5 I have read/found on the net is nearing 200k miles no issues from that perspective.

There was a guy who looked had some issues at ~20K miles but I would assume that was an anomaly. If I remember correctly, I am not sure why he took his engine apart to check the valves!

My CX-5 is close to 120K miles and I can't tell you what the valves look like. However, I can tell you that my gas mileage and overall engine performance is basically the same as it has been for the first 119.9K miles!
 
This was an odd one. If this were the norm, there would be far more pictures and video of this. There are hundreds of thousands of these engines on the road now.
Itd hard to please everyone. felixd took his time to make an intake video to show people but some is questioning his motive. :(

Heres another thread showing the condition of intake with pictures on his CX-5 by Driver 1. Again with 15,625 miles (25000 kms) it looks bad too.

Oil, Carbon build up palooza!

When we see so much oil mixes got intercepted into the catch can based on experience from Chris_Top_Her, we know these findings are legit.
 
Heres the picture of intake valves from Driver 1 at 20,525 miles even though he installed a catch can at 15,625 miles.

UPDATE: after installing catch can at 25000+km, now at 33000km+
Amazing results!!!!!! it magically cleaned the intake port and valve!
hs2eet.jpg


just kidding, i think it got worse haha
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could be that i never cleaned the intake manifold fully, i remember there was a pool of oil in when i reinstalled it (pure laziness (wiggle))
or the catch can is ineffective(uhm)
 
It*d hard to please everyone. felixd took his time to make an intake video to show people but some is questioning his motive. :(

Here*s another thread showing the condition of intake with pictures on his CX-5 by Driver 1. Again with 15,625 miles (25000 kms) it looks bad too.

Oil, Carbon build up palooza!

When we see so much oil mixes got intercepted into the catch can based on experience from Chris_Top_Her, we know these findings are legit.

I'm not questioning his motives, I question whether or not its a common issue.

This brief BITOG thread has several knowledgeable people with no issues, including a couple of techs that see lots of cars. https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/4719538/Skyactiv_Intake_Valve_Deposits

I don't know whats caused some of these seemingly uncommon level of deposits. Environmental factors and driving style may have something to do with it.
 
I'm not questioning his motives, I question whether or not its a common issue.

This brief BITOG thread has several knowledgeable people with no issues, including a couple of techs that see lots of cars. https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/4719538/Skyactiv_Intake_Valve_Deposits

I don't know whats caused some of these seemingly uncommon level of deposits. Environmental factors and driving style may have something to do with it.

Yeah, and I would even question if it has an impact. I mean, why would someone do a valve job on a car with 20-30 K miles unless it had some performance issue. I don't believe that in any of those threads did they mention why actually looked at their valves. So ever if their valves look like that, it might have zero impact. Not worth thinking about.
 
Could be that the impact of the junk on the valve does not affect performance enough to make a difference, or at least a noticable difference to most. Personally, I notice any changes in the operation of my engine and how it generally performs under a given circumstance (feel and hear, monitor gauge). I want peak power performance always.
 
Could be that the impact of the junk on the valve does not affect performance enough to make a difference

This, don't worry about a little oil in the manifold or on the valves, it does not restrict flow enough and the restriction only impacts wide open throttle if at all. The loose oil will be drawn into the engine and burned.
 
Could be that the impact of the junk on the valve does not affect performance enough to make a difference, or at least a noticable difference to most. Personally, I notice any changes in the operation of my engine and how it generally performs under a given circumstance (feel and hear, monitor gauge). I want peak power performance always.

Yeah, that was kinda my point. Even if there is build up, it is not having a negative impact on performance and fuel economy. Don't know if it is happening or not but don't really think it makes a difference.
 
Still waiting for promised picture of vacuum hose where we can spray some head cleaner into the valve area ⋯ ;)

Sorry. Here.

The easiest way for most is to simply undo the fresh air hose atop the air intake hose and spray into it.
EHjmJLB.jpg



A more thorough method (also get's into vacuum pump to clean more of the vacuum system and PCV) is pictured below. Now, I have a tee (3/8th I believe) on mine because I've installed a vacuum manifold. Stock cars will have a 90 degree elbow here that connects the larger hose at the top of the T to the vacuum pump, and the smaller hose on the left to a port that's directly past the throttle body and before the intake manifold. If you buy a pack of Tee connectors from Vatozone you can simply put the T in whenever you want to use a head cleaner, and remove it when finished. I don't even think the OEM elbow/hose uses clamps its just tension from sliding it on. The cleaner would go in on the right side (circled in red) of the tee. 8Again, the hose on the right in the picture is not OEM, and it's where you would add the head cleaner. When done, just replace the stock 90* elbow.


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Yeah, that was kinda my point. Even if there is build up, it is not having a negative impact on performance and fuel economy. Don't know if it is happening or not but don't really think it makes a difference.
Impact impact impact....
Before cleaning the intake port and valve from full tank to 3/4 of the fuel gauge, i manage to get 90 to 100km+-.
After cleaning i manage to get 130 to 140km. Im on my 4th tank since cleaning same same results nearing 3/4, getting 120km.
 
Walnut blasting is the only thorough way. Getting adapters ready for the need...if/when it comes.:)
7a6fbc90fc2888bfd012cf846d62fc8b.jpg

This photo is confusing.. you mean to tell me you/someone removed the head to access the ports? That looks like part of a rebuild.
 
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