Oil, Carbon build up palooza!

yes just installed a catch can but really surprised how much carbon buildup on a 25,000km car and look! oil dripping out the throttle body! shame on you mazda

Would I be able to check for build up by simply taking off the rubber boot and looking inside the throttle body? My Mazda has 110,000KM on it, so this much build-up concerns me especially considering this motor only has 25,000KM on it. That's very bad.

if your car is port injected yes "Italian tune up" could work but with newer cars direct injection might not really work.

That's correct, but you will still be cleaning out stuff such as your injectors, other carbon deposits within the engine, cat converters, etc with the good old italian tune-up. Try doing a full throttle pull to redline and note the very strong smell from your exhaust, if you haven't done so in a very long time. :)

BMW owners with direct injection engines have been walnut blasting their valves for a few years now to clean off the deposits. I was hoping Mazda solved that issue. May not after seeing these pictures.

This seems to be a very uncommon issue with these engines, as Mazda has taken some precautionary steps to reduce the amount carbon buildup. the 2011+ N55 motor from BMW does not have carbon build-up issues anymore however.

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.

That's right. Your best bet is to just remove the intake manifold and physically scrape the s*** off if you are experiencing carbon buildup.

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?

91 or 94 octane is not necessary, but I would suggest filling up with whatever fuel you can find that is ethanol-free, regardless of octane levels. Use the fuel system cleaner, and once getting out onto the highway with a fully warm engine do 1-2 full throttle pulls to redline, and then drive on the highway normally in 6th gear for at least half an hour.

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.

It will still make a big difference if you use it, just not for your intake valves.

Are your high grade fuels like V Power laced with detergent like ours? It keeps the inside of an engine like a new pin.

I've been using V-Power in an old BMW of mine for a long time, and was surprised to see that the engine felt far smoother when I used a fuel system cleaner.

Toyota's new 203/206 hp Dynamic Force 2.5L naturally-aspirated engine used in new 2018 Camry and upcoming new 2019 RAV4 has Toyotas D4-S port and direct fuel injection according to Car and Driver

The Camry has a good 20 HP on the Mazda 6 and more torque, two extra gears in it's transmission, and is still slower. No thanks.

The FRS/BRZ engine also came with a port and direct injection engine. The transition going from port injection to direct injection is claimed to be what is causing the torque dip mid RPM. That torque dip is what allows the Miata to win comparos against the twins. I sure hope Toyota has addressed that in their new engines.

Port injection is more efficient when cruising at a steady RPM (highway driving) and Direct injection is more efficient when idling and during full throttle acceleration, so some engines switch between the two which is great because the port injection will clean the intake valves. I could see why this may cause a dip in mid-range torque, but this has little to do with the reason why the mid-range on this engine is so s***. It's a mix between the inherit design of the flat-four engine (not as smooth, linear or rev happy as an inline engine) and the exhaust manifold is a big reasons. Upgrading the exhaust manifold on that engine has been proven to smooth out the mid-range. It's not a Toyota motor BTW, Toyota doesn't make flat-four engines. The engine is made by Subaru.
 
quick question...can't Seafoam be used to clean the intake and valves. I remember sucking it into an engine through the brake booster hose years ago to clean the upper engine. I guess these cars don't have a brake booster hose to do that??
 
I remember using a tad of ATF fluid on my TT RX-7 after it sat for a little bit. The neighbors thought my car was on fire once it cranked up :)

Ahhh those were the days!

The Seafoam cloud won't be as much but definitely noticeable.
 
Is it possible to check the condition of the intake valves without taking the intake runners off? I have a 2016 Touring and we are at 25k miles. The car has had two oil changes, at the dealer, since we purchased it (roughly 14K miles under our feet).

It is due for its 3rd oil change which will more than likely happen at the dealer in September. The car does see a fair amount of highway driving for more than 25 minutes each go, but it also sees its fair share of around town putt-putting the kid to and from school or to the grocery store and back.

Can I get a scope on the valves w/o removing the intake, or is there no other way?
 
Is it possible to check the condition of the intake valves without taking the intake runners off? I have a 2016 Touring and we are at 25k miles. The car has had two oil changes, at the dealer, since we purchased it (roughly 14K miles under our feet).

It is due for its 3rd oil change which will more than likely happen at the dealer in September. The car does see a fair amount of highway driving for more than 25 minutes each go, but it also sees its fair share of around town putt-putting the kid to and from school or to the grocery store and back.

Can I get a scope on the valves w/o removing the intake, or is there no other way?

maybe using those movie's FBI inspection cameras, remove the throttle body but is a long way to reach the furthest intake valve, i don't know frogs but its actually easy to remove the intake manifold.
 
My 2015 CX5 looks just like that with 83k miles on the clock. Cleaned it and installed a catch can. Will be using crc valce cleaner at least every other oil change.
 
My 2015 CX5 looks just like that with 83k miles on the clock. Cleaned it and installed a catch can. Will be using crc valce cleaner at least every other oil change.

Any noticeable change in performance? Any issues that made you want to check the valves? My 2013 has 62k on it but it still runs and gets the same MPG as new. I dont think Ill inspect the valves unless I have a physical symptom to investigate.
 
UPDATE: after installing catch can at 25000+km, now at 33000km+
Amazing results!!!!!! it magically cleaned the intake port and valve!
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just kidding, i think it got worse haha
102pjwn.jpg

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)
 
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
102pjwn.jpg

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)
At least you feel much better when you see so much oil mixes got intercepted into the catch can without contaminating the valves further.

I'd try 5W-30 oil and see if there's any improvement.
 
If anyone has a concern about carbon or other intake valve contamination you can easily cure ,rid or just keep the intake valves complete clean with a water/meth system. These can easily be installed in a few hours even for DIY. They are a great investment and you can remove the system at anytime and install on other vehicles.
 
Any noticeable change in performance? Any issues that made you want to check the valves? My 2013 has 62k on it but it still runs and gets the same MPG as new. I don*t think I*ll inspect the valves unless I have a physical symptom to investigate.

Yes. It idles a hell of a lot smoother. And it seems more responsive and a tad bit more power. Though that could be because of the colder temps. Didn't really notice any other issues than a rough idle. Maybe MPG but haven't gone through a full tank yet to verify.

I use what ever 0W20 synthetic is on sale for about 6500 miles. Caveat: The wife's mechanic insisted on putting in 6qt of oil for about 10 months last year while I was away. Not sure what if any role that played.
 
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Yes. It idles a hell of a lot smoother. And it seems more responsive and a tad bit more power. Though that could be because of the colder temps. Didn't really notice any other issues than a rough idle. Maybe MPG but haven't gone through a full tank yet to verify.

I use what ever 0W20 synthetic is on sale for about 6500 miles. Caveat: The wife's mechanic insisted on putting in 6qt of oil for about 10 months last year while I was away. Not sure what if any role that played.
6 qts is way too much. Manual calls for 4.8 I believe. An even 5 qts is fine.
 
If anyone has a concern about carbon or other intake valve contamination you can easily cure ,rid or just keep the intake valves complete clean with a water/meth system. These can easily be installed in a few hours even for DIY. They are a great investment and you can remove the system at anytime and install on other vehicles.

Thanks for the info Grendel65

Picking up my ride - turbo cx5 this Saturday. Would you be able to link a compatible water/meth system that would work for 2019 turbo engine. I*ve done some searching but I*m not quite sure what I*m looking at is correct. Would the dealer void warranty at all? Just tying to be proactive in taking care of my new ride. This carbon buildup problem worries me and I want to address it as early as possible if warranty stays in tact.
 
Yes. It idles a hell of a lot smoother. And it seems more responsive and a tad bit more power. Though that could be because of the colder temps. Didn't really notice any other issues than a rough idle. Maybe MPG but haven't gone through a full tank yet to verify.

I use what ever 0W20 synthetic is on sale for about 6500 miles. Caveat: The wife's mechanic insisted on putting in 6qt of oil for about 10 months last year while I was away. Not sure what if any role that played.

Yeah...that's terrible and might be why it's sounding smoother. That oil is probably frothing like a mofo when you actually drive it. Great way to kill a motor. Probably don't let that "mechanic" work on it anymore.
 
Yeah...that's terrible and might be why it's sounding smoother. That oil is probably frothing like a mofo when you actually drive it. Great way to kill a motor. Probably don't let that "mechanic" work on it anymore.

Yeah 6 qts. is definitely an overfill. Manual calls for 4.8 qts. A lot (myself included) just put in a 5 qt. jug as there's not a big difference between those volume wise. But a whole extra quart on top of that? Yeesh.
 
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