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Intake valve cleaning- anyone do this yet?

DWIL80

Hasn't posted much yet...
Joined
Apr 16, 2018
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Location
Illinois
Genesis Model Type
2G Genesis Sedan (2015-2016)
I've been researching about GDI engines and came to the conclusion that experts recommend routinely cleaning the intake valves as they will gunk up over time. CRC cleaner seems to be popular and have great results. Anyone here do this yet? I'm at 50k miles so not sure if its a good time to start now.
 
How to
 
Just a note this is a real 2 person job and the one pressing the gas needs to flutter it because you can’t hold a speed out of gear. If you try to find the perfect spot to hold it steady you get 1 of 2 outcomes - it falls back to idle or it climbs into the limiter.
 
Where did you access the intake?
 
I've been researching about GDI engines and came to the conclusion that experts recommend routinely cleaning the intake valves as they will gunk up over time. CRC cleaner seems to be popular and have great results. Anyone here do this yet? I'm at 50k miles so not sure if its a good time to start now.
I will use the CRC cleaner, but I will remove the intake manifold and allow the CRC to soak the valve stems/chambers to loosen the carbon build-up. Then I will scrub the valves and chambers clean with a brush while using a shop vac to suck up the residue. I may have to manually turn the engine to close the valves on the cylinders I will be cleaning and then alternate to the clean every cylinder.

I prefer this method because physical cleaning seems to be the only real way to remove carbon from the valve and intake runners in direct injection engines from my research.

This Audi owner is using the method I will use to clean the carbon off my valves, different engine but similar process.
 
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Whatever happened to just taking your ride out on the freeway and running her between 70-80mph for 50 miles or so and blowing the carbon out of her?
What that doesn’t work anymore with these new fangled engines?.
 
Whatever happened to just taking your ride out on the freeway and running her between 70-80mph for 50 miles or so and blowing the carbon out of her?
What that doesn’t work anymore with these new fangled engines?.
The Italian tuneup might work for port injected engines but direct injection doesn’t let the fuel wash over the valves and clean them.
 
I will use the CRC cleaner, but I will remove the intake manifold and allow the CRC to soak the valve stems/chambers to loosen the carbon build-up.
Most folks here don't have the wherewithal to remove the intake manifold and do the work. Me included, at least I don't think I do. I can change my oil and filters, hoses and such, but I've never removed parts from the engine except for an alternator back in the 80's.

So I guess is folks need to understand how to know if/when we need to take our cars in to get this work done. Is there a telltale sign we can look out for? Or every 50k miles?
 
Most folks here don't have the wherewithal to remove the intake manifold and do the work. Me included, at least I don't think I do. I can change my oil and filters, hoses and such, but I've never removed parts from the engine except for an alternator back in the 80's.

So I guess is folks need to understand how to know if/when we need to take our cars in to get this work done. Is there a telltale sign we can look out for? Or every 50k miles?
The intake manifold is only held by some bolts and hoses; so not a tough job to do. The only difficult part would obtaining the proper torque specs and proper tightening sequence from the Hyundai service manual. However, if an owner cannot do it themselves I am sure any import repair can easily tackle the job.

Signs that your engine needs a carbon cleaning would rough idling, reduced performance, lower fuel economy, and the check engine light may come on for misfires when the carbon build-up is really bad.

The VW/Audi guys has been dealing with the carbon problem since 2005 in their direct injection engines. Hence one of the reasons why I sold my old 2006 VW GLI when it hit 100k miles, plus the dual clutch (DSG)transmission was slipping due to my APR stage one tune. Carbon cleaning and new clutch packs were expensive back then.

I will perform a carbon cleaning in my 5.0 when I change my spark plugs(maybe at 80k miles) since it best to remove the spark plugs to turn an engine over manually.

Here is a shop break down on carbon cleaning and why it is important. Again different make, but same principle applies for the Genesis.
Carbon Cleaning Service for Audi & Volkswagen Direct-Injected Engines - 034Motorsport
 
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Great info there. In the meantime, I can use a quality oil, change it every 5k miles, and use a top-tier fuel. Not much else we can do.

 
I had Hyundai perform this service a few thousand miles ago. I bought my genesis with 54k miles and figured it was worth it. The dealer performs a 2 phase process. I immediately noticed better throttle response and now I'm getting about .5 mpg increase after a few months of averaging. I believe the service was $199 but varies per dealer.
 
BobBeau, at that price did they clean it with foam, or did they remove the intake manifold for a scrub?
 
They fog the system and the intake comes off for cleaning. Not necessarily in that order
That is funny. The intake manifold is removed but they do not just scrub the valves/ports while they are exposed.

Carbon is usually hard to get off the valve without scrubbing it off, therefore I doubt that a foaming cleaning session will remove majority of the carbon off the valves. However, I assume that some carbon will be loosened and removed in the foaming process with CRC due to its carbon dissolving qualities.

Personally, I will just physically scrub the crap off my valves every 80k-100k miles to be sure.
 
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I had Hyundai perform this service a few thousand miles ago. I bought my genesis with 54k miles and figured it was worth it. The dealer performs a 2 phase process. I immediately noticed better throttle response and now I'm getting about .5 mpg increase after a few months of averaging. I believe the service was $199 but varies per dealer.
Seems kinda cheap for a carbon cleaning - must have been just chemicals.
 
Take the hose off the EVAP solenoid on top of the intake.
Thanks did this yesterday, it takes longer then I thought to drain the can but I do think my engine is a little bit smoother now.
Zape, I pulled off the engine cover, there is a hose leading from one side of the intake, over the intake, then into the EVAP module on the drivers side of the engine. I just disconnected at the module then sprayed into the hose you will feel the suction from the hose when the engine is running and it does not throw a CEL. Part 28910 on this diagram: (note I'm not positive this was the same spot Sub uses but it worked for me)1589475864970.png
 
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