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. So 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 are 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.

 

[jetman]

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

additive
I've removed my intake manifold and seen how well I believe it cleaned.

 

[Patman]

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

Done!

 

[grasscutter]

Walnut blasting is only real solution.

There's actually another very effective way. You put the valve stem in a drill chuck. You wrap some maroon scotchbrite soaked in WD-40 around the valve and squeeze by hand. The valves will turn out very bright and polished looking. I've done that with small engines multiple times.

 

[Oliveoil2]

There's actually another very effective way. You put the valve stem in a drill chuck. You wrap some maroon scotchbrite soaked in WD-40 around the valve and squeeze by hand. The valves will turn out very bright and polished looking. I've done that with small engines multiple times.

This sounds brilliant. Really. If you get another 60-100k, it’s all good.

 

[dbias]

Here is my solution for IVD. MPI installed on the GTI was finished up today and software tune to make all all work right. The four new port injectors are stuffed underneath the new green fuel rail.
Upgraded low pressure fuel pump in the tank, upgraded turbo and running the wires to pin into the ECU connector and run power supply to the fuse box and it runs pretty spicy. Will be a bit of fine tuning with the tuning company after some logging of normal driving and a few 3k to 7k rpm pulls and it should be well over 400 whp.

 

[Snagglefoot]

So let’s see what GM has chosen for the new 2027 V-8 engines. If they go back to port injection or a combo with direct and port injection there is merit to the issue. If they just use direct injection like the 2026, might as well yell at clouds.

 

[grasscutter]

Done!

Thank you. Very much appreciate it.