Direct Injection Valve Cleaning Maintenance

[RayCJ]

Hi Folks... I'm new here so please let me know if this not the right area to post this.

I have a brand new Mazda3 with a 2.5L Direct Injected engine. I'm loving it so far. Fuel economy is out of this world given the performance it can deliver when called upon.


There's a lot of buzz out there about valves gunking up on engines with only direct injection. There are products and services dedicated to cleaning the back-sides of the valves. Mazda has been making some really nice motors in the last couple decades and I'm having a hard time believing they would produce an engine that has a known serious characteristic flaw. The owner's manual does not mention any procedures related to regular valve maintenance.

How big of a problem is this with Mazda engines and/or with other engines?

I'm thinking about doing preventative maintenance at each oil change using CRC's product aimed specifically at this (https://www.autozone.com/fuel-and-e...-gdi-idv-intake-valve-cleaner/461563_0_0) but not if these are solutions to problems that don't exist.


Thoughts ???

Thanks

Ray C

 

[Ducked]

I'd use petrol. Its cheap (in the US) and it was the solution to this problem before it was a problem.

(If it is a problerm)

 

[skyactiv]

My wife had a 2012 Mazda3 with a 2L engine and a 6 speed manual. What was odd is that it got better gas mileage when new compared to when she traded it in.

I wouldn't worry about the intake valves until you have a MPG drop or drivabilty issue concerning it which may or may not ever happen.
The concern I have with using CRC and such products is that loose pieces of loosened carbon can potentially scratch up the cylinder walls
and lower the compression.

An example might be having 4 cylinders reading around 185 PSI not ever using the product vs having one cylinder reading 185 PSI, another reading 170 and
the other 2 reading 180. Hypothetical of course.

Some early adopters of the technology had more issues than others such as Audi and VW.

Some Toyota and Lexus vehicles and even the 2nd gen 3.5 Ecoboost in the F150 use both port and direct injection which
solves the issue.

Removing the intake on most four cylinder engines and cleaning the intake valves is not very difficult.
I cleaned the intake valves on my GTI once.

I learned the Skyactiv engine in the video below has a factory oil catch tank.

 

[Oildudeny]

I'm driving a direct injection Mazda power plant over 2 yrs with no issues. Just run top tier fuel and my personal preference is 3x year run a bottle of chevron with techron.

 

[skyactiv]

Originally Posted by Oildudeny
I'm driving a direct injection Mazda power plant over 2 yrs with no issues. Just run top tier fuel and my personal preference is 3x year run a bottle of chevron with techron.


Doesn't do a thing for the intake valves unfortunately.

 

[Jimzz]

What I tell people to do is every other oil change or every 15k, which ever comes first, is to spray out the intake/throttle body with regular cheap carb/intake cleaner.
But every 30k or so to use the stronger CRC DI cleaner.

I don't think Mazda/Ford has as big an issue like most European cars or the Lexus/Toyota 2.5 motor. But if you plan to keep a long time its cheap and easy maintenance.

 

[buster]

I don't think Skyactiv engines have the intake valve deposit issues. I'm at 54k on a 2.0L. I haven't noticed anything that would indicate there are deposits, but I haven't looked either. Quite a few people have put well over 100k miles on these engines with no issues.

 

[walterjay]

I CRC my Hyundais once a year. That translates to about every 15,000 miles. I do it as a preventive maintenance. Very easy job.

 

[StevieC]

There is a first generation Hyundai Veloster in my family and it's now a high mileage engine with Direct Injection. It suffered from enormous valve gunk when first new and ever since every oil change we have been using the CRC product through the throttle body and the problem has not come back.

Although I haven't seen this issue on Mazda direct injection it might be a good idea to still do it once an a while to keep the levels down in case they are building up over a longer period of time. Just my advice and nothing more. There may be some benefit from a catch can on the PCV as well but this has mixed results and no one is 100% sure it will cure a valve build-up situation. I'm testing a can on my new Toyota.

I would also use a good quality synthetic and something with a great Noack rating because this appears to help the situation. Like Valvoline Modern Engine or similar.

It also doesn't hurt to use a high quality PEA based fuel system cleaner in the fuel tank regularly to keep the injectors as clean as possible and operating at peak efficiency as they can clog up being in the combustion chamber exposed to the higher temperatures and and injectors not operating at peak efficiency can cause it to not run as efficiently and/or contribute to things like fuel dilution in the oil.

Not trying to scare you, just offering some advice to get the best maintenance out of your system as possible. You have a really nice ride there. I just encouraged a friend of mine to buy a Mazda because it fit her needs and they have some really good engineering now.

 

[dave1251]

Originally Posted by skyactiv
Originally Posted by Oildudeny
I'm driving a direct injection Mazda power plant over 2 yrs with no issues. Just run top tier fuel and my personal preference is 3x year run a bottle of chevron with techron.


Doesn't do a thing for the intake valves unfortunately.



Fortunately it does. PEA does survive the combustion process and provides prevention of buildups and slight cleaning.

 

[ffhdriver]

How does "surviving the combustion process" have any effect on the intake valves?

 

[StevieC]

Originally Posted by ffhdriver
How does "surviving the combustion process" have any effect on the intake valves?


As I understand it, some of this slips past the rings as crank case vapor and gets fed back via the PCV where it can be effective. It also gets into the oil which is further fed back via the PCV in more vapor and I think this is how it can have some effect. Not as strong as if it was being sprayed across the valve in a PFI setup though.

Again this is how I understand it from various reading I've done. Others can confirm.

 

[Pew]

I have the Ford 3 cylinder 1L engine (it's at this moment tears should be shed for me) which is a TGDI, and according to this patent:

https://patents.google.com/patent/US6178944
Quote
"A control method and system is described for a spark ignited, four-stroke engine having multiple combustion chambers, each coupled to at least one intake and one exhaust valve, a fuel injection system for injecting fuel directly into each combustion chamber, and an electronically controlled throttle for throttling air inducted through an intake manifold into the combustion chambers. Comprising:

1) Detecting when to initiate an intake valve cleaning;
2) Indicating when the engine is operating in a homogeneous mode wherein the throttle is partially closed and fuel is injected during an engine intake stroke to generate a homogeneous air/fuel mixture; and
3) in response to said valve cleaning detection and said homogeneous mode indication, injecting additional fuel during a valve overlap of the intake and exhaust valves so that fuel is drawn into the intake manifold and subsequently inducted back into the combustion chamber past the intake valve.

 

[StevieC]

This is in later DI engines (the first gen Veloster in our family doesn't have this update) and Ford by far has the best control out of this it would seem when DI alone is used. However it's hard for the engine to detect when unless it's on some sort of cycle timer and things like high Noack oil and poor quality fuel might affect this. Keyword might.

 

[k1xv]

I agree that the primary source of the intake valve deposits is crankcase oil vapors, and, if the crankcase is overfilled, some actual droplets of liquid oil.

So one, I try to make sure the crankcase is not overfilled, or even filled to the upper line on the dipstick.

And second, it sounds as if, to have any effect on intake valves, a cleaning additive would have to be in the motor oil, not the fuel.

Maybe, someday in the future, engines will have a tank for intake valve cleaner, and pump it into the intake ports. Similar to diesel engines now using diesel exhaust fluid as the engine runs.

 

[buster]

http://www.motoiq.com/MagazineArticl...echnology.aspx

"To eliminate the problem of intake valve deposits that plague current direct gasoline injection engines, the engineers at Mazda determined that deposits are formed when intake valve temperatures fall below 400 degrees C. Measures were taken so that the intake valve would operate above this point to reduce deposit formation."

"One of the biggest issues with direct injection engines is a build up of deposits on the intake valve. Mazda determined that this was largely due to the intake valve being too cool. A lot of analysis went into designing the heat paths away from the valves to keep them at the proper temperature to avoid deposit formation."

 

[RayCJ]

Hey folks, really great information and feedback to my original post. This is a nice group.

I had a feeling this problem was under control -at least as far as recent-production Mazda's are concerned. The SkyActive-G 2.0 and 2.5L engines have been around since 2010/2011 (test versions) and 2012 (production version) and Mazda's reputation would have dropped like a rock if this issue was not resolved.

I take good care of my vehicles and do not make strong demands on engine performance (but once in a while, the devil whispers in my ear). It seems to me that if someone is jumping on it constantly and letting the oil get thin, there will be more blow-by and thus, more accumulation on the back of the intake valve. Since Mazda seems to have a solution and since I treat the car with respect, I'm hoping to avoid this problem. I'll keep an eye on it and will consider doing a CRC treatment at oil changes -maybe.

Thank for sharing thoughts...

Ray

 

[MobilinHyundia]

That CRCÂ valve cleaner works good. Just follow the instructions on the can.

 

[StevieC]

Originally Posted by RayCJ
Hey folks, really great information and feedback to my original post. This is a nice group.

I had a feeling this problem was under control -at least as far as recent-production Mazda's are concerned. The SkyActive-G 2.0 and 2.5L engines have been around since 2010/2011 (test versions) and 2012 (production version) and Mazda's reputation would have dropped like a rock if this issue was not resolved.

I take good care of my vehicles and do not make strong demands on engine performance (but once in a while, the devil whispers in my ear). It seems to me that if someone is jumping on it constantly and letting the oil get thin, there will be more blow-by and thus, more accumulation on the back of the intake valve. Since Mazda seems to have a solution and since I treat the car with respect, I'm hoping to avoid this problem. I'll keep an eye on it and will consider doing a CRC treatment at oil changes -maybe.

Thank for sharing thoughts...

Ray


It is my opinion that OE's like Mazda and Ford to name a few, have it figured out completely in their direct injection setups in their latest engines and as long as a top-tier fuel is used along with a PEA fuel system based cleaner once and a while and the engine is kept maintained with good spark-plugs and regular oil changes using a quality oil and thromped on once and a while on the highway and not driven gently all the time it should be just fine.

Other OE's like Toyota (just to name one but there are others) took a different approach and went with a Dual Injection setup where they have a both Port injection and Direct injection on the same engine and fire both at the same time most of the time or just the direct injection injectors at other times. This ensures the valves are always being washed but also gives great performance and economy.

There are other OE's out there that seem to pretend the problem doesn't exist and they are above fixing their engines and far more costly maintenance like expensive valve cleaning using crushed walnuts shells and/or other cleaning techniques.

It also depends on what generation engine you have from which OE just to complicate matters.