Carboned Intake Valves

[Al]

Has not been discussed for a while. Is there anything better than CRC other than walnut blasting.

 

[dkryan]

Make/model/year and current mileage?

Or is your post an “in general, what’s the latest and greatest in cleaning intake valves?”

 

[JunkdrawerDog]

There's a remedy for that. Port fuel injection. Either alone or paired with GDI.

 

[fantastic]

Start filling up at your local BP that advertises Top Tier +

 

[theMM]

I've heard about people using dry ice to blast off carbon deposits off the intake valves in DI engines. Downside is that Dry Ice is expensive... But it works pretty well from what I have seen.

 

[Wheel366]

Someone told me that they believe that Berrymans is better than CRC. I have no experience yet.

 

[TheMAN]

Regardless, I don't advise using that with a Mazda SkyActiv engine... because it's an Atkinson / "Miller" cycle engine, they have very little vacuum at idle... whatever you spray past the throttle body ends up puddling inside the intake manifold... if you try to do the "italian tune up" right after, that stuff ends up getting sucked into the engine for real and massive detonation / unmetered low octane fuel gets burnt immediately and instant limp mode... I got smarter the last time I did it... drove it like driving miss daisy and took it on a 30 mile freeway run, but even some moderate acceleration, you can hear the engine ping, but it was still within its tolerances, so no freak outs... it took that much driving to get rid of the CRC cleaner... not worth the trouble for me

 

[grasscutter]

Full time port fuel injection is the best way to keep the valves clean.

Don't buy a car with GDI, AFM, or VVT. Just say no to unnecessary complexity.

E D I T

I hope this thread gets moved to the Mechanical/Maintenance Forum.

I didn't know I was in the PCMO Forum.

I take pride for not posting there.

 

[jetman]

Full time port fuel injection is the best way to keep the valves clean.

Don't buy a car with GDI

Techron and port injection

 

[buster]

Has not been discussed for a while. Is there anything better than CRC other than walnut blasting.

I don't think so. I'd use VRP and do a few WOTs or run the engine at 4k rpm sustained just to see if it could clean them up a bit. Likely not but worth a shot? There was an method VW put out years ago that was similar to the high sustained rpms for a period of time to help with IVD.

 

[grasscutter]

Techron and port injection

You talking about buying the additive bottle or the actual gasoline?

 

[edyvw]

Walnut blasting is only real solution.

 

[Mainia]

I don't think so. I'd use VRP and do a few WOTs or run the engine at 4k rpm sustained just to see if it could clean them up a bit. Likely not but worth a shot? There was an method VW put out years ago that was similar to the high sustained rpms for a period of time to help with IVD.

BEFORE I had 5 OCI of Valvoline Restore and Protect, I pulled my manifold to see how bad my valves were and I had small donuts rings on the valve stems just below the valve guide, 2 years-ish later I had full time micro idle misfires. I had to do a walnut blasting and those small donuts were flattened a bit but still there, everywhere else it had more carbon then the first look. SOo did VRP help? Micro kind of.........but not enough to really matter, because the carbon still progressed. Walnut blasting in my book is the ONLY way to clean the valves when you to my level of idle robbing smoothness, If you just have one GDI injector per cylinder. I tried CRC 3 times through the cars life. 74,500 miles on the car on walnut blasting day.