Best way to clean valves on this direct injection engine?

[R18Civic]

2019 Chevy Malibu

'm wondering. I thought chevron techron would be enough to clean engine out but since the engine is DI it seems that isn't the case.

Is there a chemical I can use to clean the intake valves out with? And how would I go about doing so without removing the intake?

 

[PandaBear]

You probably should go to a chevy malibu forum to get more specific suggestions. I know the only universal DI valve cleaning that will guarantee to work is walnut shell blasting. Some cars don't have that bad of an issue so they won't need it, but others do.

 

[WobblyElvis]

I have had 2 cars with DI engines. First car went to 250,000 miles, I bought it with 120,000 miles on it. Second car bought with 85,000 miles on it, now has 155,000 miles. They both run fine with no cleaning of the intake valves. IMO the best way to clean the valves is to not do it.

 

[Urshurak776]

You could get that stuff you spray into the intake. Not sure how well it works.

Is there an issue?

 

[R18Civic]

You could get that stuff you spray into the intake. Not sure how well it works.

Is there an issue?

No just trying to ensure the car stays in top shape. It was a big investment.

 

[buster]

It seems that most that don't clean them never have noticeable problems. With that being said, try Valvoline Restore and Protect and take it on a highway drive. Keep rpms at 4k for about 20 minutes. Worth a shot.

 

[ls1mike]

I can tell you MOST GM DI cars don't seem to have a problem with the carbon issue.

 

[Urshurak776]

It seems that most that don't clean them never have noticeable problems. With that being said, try Valvoline Restore and Protect and take it on a highway drive. Keep rpms at 4k for about 20 minutes. Worth a shot.

I don’t think that would do a thing to the valves. Maybe some oil vapors from the PCV will get on them. Won’t hurt anything to try though.

 

[DuckRyder]

What ls1mike said not withstanding, DAP did a couple of videos on YT on this (on VWs) and the basic conclusion was manual cleaning.

 

[skyactiv]

This is a what you don't know wont hurt you thing. I wouldn't want to break off any carbon and possibly scratch up the cylinder walls.

 

[buster]

I don’t think that would do a thing to the valves. Maybe some oil vapors from the PCV will get on them. Won’t hurt anything to try though.

You're probably right. I'd be curious to see if it worked. Based on the VW study and fact that VRP seems to clean whatever it comes in contact with, I do wonder if it would slowly work.

 

[Leo99]

I haven't been keeping. Is the transmission in this car fixed?

 

[f355spider]

I have had 2 cars with DI engines. First car went to 250,000 miles, I bought it with 120,000 miles on it. Second car bought with 85,000 miles on it, now has 155,000 miles. They both run fine with no cleaning of the intake valves. IMO the best way to clean the valves is to not do it.

I think a better take is "clean the intake valves on a DI engine when required, or necessary".

Generally that will be when you notice unexplained gas mileage drop, a check engine light or other anomaly that would dictate additional investigation that determines intake valve deposits are the cause.

 

[MurkyAsparagus]

The best way to clean the valves is walnut blasting. A lot of the sprays that claim to clean them are subpar IMO.

 

[Wylie6G72]

Best way to avoid issues is to do the work and take the intake off. I used CRC Intake Valve Cleaner and a wire brush to clean the valves on my Focus ST, and I can tell you that just spraying it into the intake of a running engine is not going to do anything. That stuff has to soak and turn the carbon into tar, then into liquefied tar, so it can be vacuumed out. I made multiple passes on each cylinder..... Flood the port, let it soak, scrub, vacuum.

Something additional to note is that if the CRC does actually work on the running engine and chunks of that carbon break loose, your turbo could suffer. Best plan is to take the carbon out through the intake, not send it through the exhaust.

 

[Nessism1]

 

[SC Maintenance]

Nothing sprays on the valves to begin with which is why some of them carbon up.

How is this car actually used? Stop and go / short trips seems to be the hardest on DI.

Walnut blast is the safest since the carbon comes out dry with the walnut shells. You can gear up to do it yourself, or just pay the dealer when / if it needs it ever.

 

[R18Civic]

I haven't been keeping. Is the transmission in this car fixed?

There was never anything wrong with it. "Cvt going bad dealership" was just out for quick 6 thousand bucks

 

[R18Civic]

Nothing sprays on the valves to begin with which is why some of them carbon up.

How is this car actually used? Stop and go / short trips seems to be the hardest on DI.

Walnut blast is the safest since the carbon comes out dry with the walnut shells. You can gear up to do it yourself, or just pay the dealer when / if it needs it ever.

It's a lot of short drives. In live 15 minutes from work, however I do make it a point to drive about 50 miles one trip on every fresh tank.

 

[f355spider]

The best way to clean the valves is walnut blasting. A lot of the sprays that claim to clean them are subpar IMO.

YouTube videos prove sprays don't work...it requires some sort of mechanical action...usually media blasting with walnut shells.