2018 CX-5 Carbon build up?

[AndrewSS]

Is the 2.5NA known for carbon buildup on intake valves? We just hit 100,000km on ours and I’m wondering if walnut blasting is worth looking into.

 

[Mazdiod2]

I've read that Mazda incorporated design into the engine to prevent carbon buildup. Are you having issues or symptoms that make you believe your's has carbon buildup? Some have reported this issue on this forum in the past.

 

[AndrewSS]

I've read that Mazda incorporated design into the engine to prevent carbon buildup. Are you having issues or symptoms that make you believe your's has carbon buildup? Some have reported this issue on this forum in the past.

No, but I know GDI engines are susceptible to build up. And it looks like a pain in the ass to install an oil catch can so I never did. But it sounds like from what you’re saying there may be an internal catch can already

 

[cz5gt]

Most important is to drive the car longer distances frequently not just city drive idling. Plus regular oil changes and high octane fuel usually helps minimize the effect. Any GDI without extra port injectors (Toyotas have them) is prone to that sooner or later.

 

[ceric]

AFAIK, Mazda did two things to alleviate carbon buildup.
1. oil separator
2. allow high temp near intake valve (less buildup)

Still, you can find some pic w/ some carbon buildup, but not as bad as some other brands'. Some people invest on catch can to reduce it. Not sure how effective that is.

If I could find a shop near me that does walnut blasting for reasonable $$$, I would have it done.
I haven't found one, so far.

 

[N7turbo]

I read too many horror stories after catch can installs so I crossed that off my list of mods to do.

 

[ceric]

I told my indie shop friend that he should invest on doing walnut blasting... I can refer a lot of business to him.... adapters for brands/models... etc.
With EVs taking market share, his business is not booming ....

 

[gman1]

My 2018 CX-5 non-turbo has 130,000 miles on it and went into limp mode on the highway caused by cylinder misfire. The shop said one of the spark plugs and coil went bad. I had replaced all the spark plugs at 75,000 miles so only got 55,000 miles on the ones that went bad. I got 4 new spark plugs and replaced the bad coil (the other 3 coils were fine) and drove back home and the same CEL and engine issue happened right away. I took the car back to the shop and they said its due to carbon build up. The CEL apparently comes on when you start the car after it has been sitting idle for a few hours and then goes away once the engine warms up. Because of this, they are thinking I have carbon build up in the valves causing the misfire. They recommend the BG 3 step cleaning and possibly taking the valve apart and seeing how bad the build up is. I only use shell gas and oil changes from the dealership. I didn't have issues with performance and was getting 28-29 mpg during fill-ups. I wonder if carbon buildup can cause this without other underlying issues prior. I am still figuring this out so not sure if the carbon buildup is the culprit.

 

[Mazdiod2]

Do you know what the code was?

 

[gman1]

Do you know what the code was?

 

[gman1]

Hmmm..the shop just sent these pictures back to me of my valves. Is it really

as bad as how it looks on the picture.

 

[N7turbo]

My 2018 CX-5 non-turbo has 130,000 miles on it and went into limp mode on the highway caused by cylinder misfire. The shop said one of the spark plugs and coil went bad. I had replaced all the spark plugs at 75,000 miles so only got 55,000 miles on the ones that went bad. I got 4 new spark plugs and replaced the bad coil (the other 3 coils were fine) and drove back home and the same CEL and engine issue happened right away. I took the car back to the shop and they said its due to carbon build up. The CEL apparently comes on when you start the car after it has been sitting idle for a few hours and then goes away once the engine warms up. Because of this, they are thinking I have carbon build up in the valves causing the misfire. They recommend the BG 3 step cleaning and possibly taking the valve apart and seeing how bad the build up is. I only use shell gas and oil changes from the dealership. I didn't have issues with performance and was getting 28-29 mpg during fill-ups. I wonder if carbon buildup can cause this without other underlying issues prior. I am still figuring this out so not sure if the carbon buildup is the culprit.

I think it's possible. But it should be verified with a camera before committing to a fix. Which, at 130,000 miles, I would suggest removing the head and having it walnut blasted. Then you'd be 100% clean for the next 100k+ miles. You'd also get a new head gasket out of it.

Edit: just saw the pictures above. Definitely do the walnut blast. That's pretty bad.

There may also be a way to do the walnut blast without removing the head—I suppose one port at a time with the valve closed. I'm not sure which way is standard procedure.

 

[Silly Wabbit]

Mazda Direct Injection Valve Cleaning Tool

The perfect tool for the DIY Mazdaspeed 3, Mazdaspeed 6 or any other direct injection engines for media blasting valve to remove carbon build up.

corksport.com

 

[gman1]

I think it's possible. But it should be verified with a camera before committing to a fix. Which, at 130,000 miles, I would suggest removing the head and having it walnut blasted. Then you'd be 100% clean for the next 100k+ miles. You'd also get a new head gasket out of it.

Edit: just saw the pictures above. Definitely do the walnut blast. That's pretty bad.

There may also be a way to do the walnut blast without removing the head—I suppose one port at a time with the valve closed. I'm not sure which way is standard procedure.

I couldn't find anyone who does the walnut blasting around Dallas area. Everyone does the BG 2 or 3 step induction cleaning. Anyone have experience with that versus walnut blasting?

 

[madar]

Post on DIY walnut blasting, you don't have to remove the head...

Cleaned the intake valves on my 2013 CX-5

 

[HyFlyer]

... the shop just sent these pictures back to me of my valves. ...

That looks about what I would expect at 130,000 miles.

Your shop has it opened up enough to clean the valves right now. Just have them clean them.

 

[gman1]

That looks about what I would expect at 130,000 miles.

Your shop has it opened up enough to clean the valves right now. Just have them clean them.

. The shop took a picture of my blown spark plug and was all too willing to charge me an hour of labor to put the new one in versus no charge to put the old one back on.

 

[gman1]

Post on DIY walnut blasting, you don't have to remove the head...

Cleaned the intake valves on my 2013 CX-5

I took it to the dealership for the BG 2 step. I showed him the picture of the gunk valve and he show the BG rep who said "no problem, it will all come off after the cleaning" so we will see. Something tells me the CEL might not be due to the gunk since that's been there for some time.

 

[Silly Wabbit]

Did the shop replaced the 4 spark plugs and 1 coil with OEM parts?

 

[gman1]

Did the shop replaced the 4 spark plugs and 1 coil with OEM parts?

They put in the ngk plugs and ngk coil. I bought 3 more coils to replace myself for less than the 1 they put in. waiting for the CEL issue to resolve first.