Detailed explanation is available on YouTube!
Our shop started auto maintenance in September 2022.
The case where soot accumulates in the intake of Mazda diesel is
I didn't know much about it until October of last year.
While cleaning the intake and EGR of BMW and Toyota cars,
The CX-3 happened to be brought in with the check light on.
The DPF regeneration interval is unusually short, and the injector learning correction is
From the data values that are completely negative
・Is soot generated during combustion increasing?
・Is there a lack of intake air due to soot buildup in the intake caused by EGR?
・Isn't the intake of Mazda cars the same?
I started disassembling it from that prediction, and bingo! was.
Now, people come from far away places such as Kanto, Tokai, Hokuriku, Tohoku, and Hokkaido.
We are now receiving many requests for cleaning work.
Mazda cars are the only ones being talked about as if they are a big problem.
It's just that no manufacturer's diesel gets much attention.
Various problems are occurring due to the same phenomenon.
This time CX-3 SKYACTIV 1.5D mileage 140000km
We came to our store from Chiba Prefecture for intake/EGR carbon cleaning.
The contents of this time can be completed in 1 night and 2 days.
I'll diagnose it right away.
The DPF regeneration interval is as short as 5 to 60 km.
Injector learning correction value
The correction is quite negative.
Control is in place to reduce the amount of injection.
Negative correction = rich mixture = insufficient intake air
This is a data value that indicates that the intake is clogged.
Insert the camera into the intake manifold!
It's going to be pretty tough this time too...I'll break it down.
It came off. It's quite a blockage.
High pressure EGR = includes soot
Low pressure EGR = soot-free
The 1.5D has this kind of control, unlike the 2.2D.
According to past verifications, the higher the usage rate of high-pressure EGR in a vehicle, the more
The intake tends to become clogged.
There are many cases where oil leaks from the joints of the resin molded parts.
Although it is reusable, it is cheap, so it is basically replaced.
High pressure EGR valve. It is covered with hard carbon.
It seems that it may peel off and get stuck in the valve seat, causing problems.
(It looks like it's also being recalled)
Confluence point of EGR and fresh air
Intercooler entrance side. It is water-cooled.
Low pressure EGR flows from before the intake cooler.
The air flowing from the low pressure EGR is after passing through the DPF.
There is no sootiness at all.
It seems to be quite clogged with oil mist from blow-by gas.
Intercooler outlet side. It's dirty with soot.
At first glance, is it regurgitation? That's right.
High-pressure EGR containing soot flows immediately after this exit side.
In the reverse direction by controlling the shutter valve such as accelerator ON/OFF.
It is thought that soot has accumulated when the pressure fluctuates.
Inside the port.
It's about 1/3 full.
Around the valve. Something I don't understand anymore.
Let's clean it!
It turned black in a few hours.
After preparing the intake port by scraping and suction
Finished with walnut blast.
This is a time-consuming process.
By eliminating carbon around the intake valve
It has the effect of reducing engine noise peculiar to diesel engines.
The intercooler fins are quite soft.
Finally, wash while adjusting the pressure.
Each part after cleaning. Like new.
shutter valve and
The EGR valve must be cleaned manually.
Assemble a new intake manifold.
Vacuum coolant filling
After steam cleaning, reset each PCM data
DPF forced regeneration
Injector forced learning
After completing the work, we will do a road test.
・Improved accelerator response
・Decrease in accelerator opening
・Improved fuel efficiency
We receive information from users after the work is completed.
I make various discoveries every time I run while checking the data.
By the way, this CX-3 and the one before work
・DPF regeneration interval
・Injector learning correction value
Here is the data after 4 months and 7000km driving on a CX-3 under almost the same conditions.
Both DPF regeneration interval and injector learning correction value
We have confirmed that the data is firmly pointing in the direction of improvement.
This is thought to be due to improved combustion efficiency and a reduction in the amount of soot generated during combustion.
The phenomenon of soot accumulating in the intake is not a malfunction or malfunction.
Due to the structure of diesel engine EGR, this cannot be helped.
What has accumulated will not fall out at the intake pressure level.
The only way to fundamentally remove it is to physically clean it.
By cleaning it, you can restore it to its original performance.
Not just soot buildup in the intake.
For diesel engines, the balance of auxiliary equipment is extremely important.
By constructing them at the same time, you can correct the imbalance to the maximum extent possible.
long! Happily! Stay well!
For users who want to associate with Mazda diesel vehicles
We provide various cleaning services.