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Discussion Starter #1 (Edited)
Due to the nature of direct injection, these engines will accumilate a large amount of carbon build-up over time. The only way to remove it is manually scrubbing, or media blasting the valves. Using seafoam/engine cleaners/ect will not do anything measurable to this buildup, this cleaning is basic maintenance in order to keep your engine running at its best.

Do this every 40k miles, and I also recommend deleting the EGR valve, swapping your PCV valve, and installing an OCC kit at this time to keep the intake manifold clean
Guide to Preventative Maintenance and Modding

Links to info on DI and other DI cars, showing how common it is for the industry to clean:
Carbon Build Up Info
VW Golf
BMW
*Note: BMW/VW/COBB all offer valve cleaning at their dealerships, among other places- it is an industry standard to clean them

Why clean? Better performance (recovered flow), smoother idle, smoother driving, save money, and to learn about your car!



Here is the best method for cleaning your valves: before/after soaking/after a little blasting



Equipment needed: (noted below, with pics)
  • An air compressor setup
  • Media gun/abrasive gun (open/close valve-but not necessary)
  • Fine walnut media **Note: HF has a different categorization than other places for the grit on the media**
  • B12 -2 cans (1 could do, if you are tight on cash)
  • 1' section of clear hose from Home Depot - 1" ID, available by plumbing
  • A towel you can sacrifice
  • Two way fluid transfer pump
  • Masking tape
  • Safety glasses/gloves (IMPORTANT)
  • Camera- to brag once you are done
Brief Overview of procedure:
  1. Remove IM, followed @jbarone instructions (here)
  2. Ensure which 2 valves are TDC- top dead center/closed
  3. Soak those valves in B12 for at least 1 hour & cover other valves with masking tape
  4. Suck out majority of B12 using two-way fluid pump
  5. Air blast valve to remove remining B12, while using a towel around gun tip to catch carbon/B12 coming out (goggles/gloves on) (90psi for all air use)
  6. Blast valves with media in 2sec pulses for 30sec, vacuum on, repeat until happy
  7. Suck out media with small hose, then air blast for 10sec to remove anything else
  8. Tape over cleaned valves
  9. Proceed on other valves in same order (TDC/soak/suck/blast/clean)
  10. Photoshoot
TOTAL COST, without air compressor = only ~60 bucks, and you have 24.8/25 pounds of media left to help many others and clean again!

In order to achieve these results, the process goes as follows:

STEP 1
Soak 2 TDC-top dead center valves in B12 (maybe-substitute denatured alcohol/seafoam/methanol)
Top dead center is achevied by removing the passenger front wheel, then a little plastic guard which is held on by 3 plastic screw-you can't miss it, then you will see this:


The (14mm) tensioner pulley is on the left-turn this clockwise to loosen the tension on the belt before/after messing with the PS pump. You will need someone to remove the belt from the PS pump as you relieve the tension

The (21mm) crank pulley is on the right, turn clockwise to turn the engine, it will be at TDC when it gets toughest to turn (check valves are TDC by looking, then pouring some B12 in and see if it stays put)

**Note: Only 2 valves will be entirely TDC at a time. On mine, one valve was 90% closed, so take note for next time (ie- valves 2/4 and 1/3 are TDC grouped for me)

Open valve


Closed valve


**Note: I do recommend removing the belt from the power steering pump before turning the crank pulley (before tilting the PS pump to the side during the Intake Manifold removal is even better), but it is not needed

STEP 2
After soaking the TDC valves either overnight (prep night before), or for 1+ hours, use either your shop vac (if you wish to ruin the filter and spend time cleaning it-trust me on this) or a two way fluid transfer pump (Here: 5 bucks at HF) to suck out as much B12 as you can into a container

Now take your gun, wrap the towel around the tip. Now insert/jam it into the valve to AIR blast all the leftover B12 out (it will shoot out, so wrap the towel in layers to make it thicker, and apply pressure)
**Note: Always use safety goggles and some gloves


STEP 3
Now, apply the one foot section 1" clear ID tube from Home Depot ($2) into the valve runner, as in this picture:

**Note: I soaked one valve for only ~1hr and got the same results, but it took a whole 2-3 minutes longer to clean!

I drilled a hole just small enough for my gun tip to fit into, roughly 1" from the base of the tube, then I stuck the gun/hose into the valve runner and apply the vacuum cleaner/shop vac to the open end.
I blasted at 90psi-the gun max operating pressure (BMW instructions say 6 bar, which is 116 psi BMW Link)

Blasting was done in pulses of 2sec for about 30 seconds total, then the valves were nearly spotless! Of course, I kept going to make them shiny and pretty, but honestly, this can be done on all the valves in under 10min.

**Note: I turned the vacuum on periodically to suck up excess media, since the tube collects much of the media. Keeping a vacuum on a "low" setting throughout the blasting could also be done, but you will use more media, as noted below. I also held the gun sideways (hood-style) to avoid any jamming, which worked best.

Unlike the prior write ups, I used a gun from harbor freight which had an open/close valve for the media. This allowed me to only blast air, which cleans very well on its own. This also allowed me to use less than 1 hopper of media for ALL the valves (out of the 25 pounds I got from Harbor Freight). Blasting only air into the valve periodically in essence reuses the media which is laying down there; think of it as a balloon which you let loose in a box-it smacks into everything. Another great point of using this gun was the ability to air-clean the engine bay, since 100% of the media is never going to be contained.
Gun used:
Gun has standard 1/4" air hose fitting and was sealed at the threads using tephlon tape (standard air tool procedure according tpo the neighbor)

This is what my setup looks like, note the vacuum attached on the end:


STEP 4
After blasting was to my liking, I stuck a small plastic hose attached to my vacuum into the valve to suck up any excess, then I blasted the valve with AIR for 10sec to clean anything remaining out (although it would just burn off, walnut is combustable).

**Note: cover the finished/remaining valves with masking tape to avoid any richochet media going in. I also taped the gun's hopper closed since I was holding it at all angles


That's it guys, let me know if you want clarification on anything. As a sidenote, you could probably acheive very clean valves simply by using the air and soaking (as noted in this thread, post #15) Props to @timjs for inspiration on this project. I think B12 does an identical job to the Mazda Zoom Zoom Cleaner, possibly in a less concentrated form; but, nonetheless, it is just as effective for a fraction of the cost. Zoom Zoom Cleaner is originally designed for rotary engine cleaning, link to RX8 forum info

I used the liquid B12, since it is cheaper and the spray does nothing we need


Got clean valves yet?
 

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Awesome write-up.....thank you! Added to the carbon build-up thread.
 

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Excellent how-to, very much mustache approved!

I love the way your clear hose trick ended up working, gracefully split the difference between cheap, simple and damn effective! Very well done Sir!

This will become my default method for valve cleaning, no doubt. FOr me, twenty minute soak with DA, then blast using the awesome clear tube.

Great work.
 

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WOW! Great write up! I plan on doing this in a few weeks and your method couldn't have been written any better nor made any simpler. Thanks! :thumbup: :)
 

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Vote for a sticky. I've been neglecting this for a while. Just did my EGR delete so no excuse not to clean my valves now as it should only be one time deal...

Sent from my Galaxy Nexus using AutoGuide.Com Free App
 

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Nice write up! Added to "How To" section of the FAQ Sticky.
 

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Lowspeed
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Holy fuq, who the heck are you and how did you get in here???

There used to be a guy with your screen name around here, but pretty sure he died....
:D :D
 

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Soaking the valves right now, results at 10pm ;). Thanks again oh_yeams6 for this perfect solution!
 

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My HF media blasting gun is not working correctly. The walnut media is not flowing well. I took the hopper off to see if the hole was blocked and it appeared to be blocked by a small piece of plastic(removed blockage). Put the hopper back on and tried again.....no luck.Took it off again and decided to increased the size of the hole with a drill bit. Tried again and still not working correctly. Fudge. The hopper has a small hole on the side of the piece that goes into the gun.....maybe the cause of my problem? damn-it. I've tried everything and no luck so far
 

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Where did you get the walnut media from? In OP's notes he states "HF has a different categorization than other places for the grit on the media" so I wonder if you have a particle size that is not compatible with the gun?
 

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I tried everything.....I even did a handstand. I returned the blaster and got two different types of blasters. One of them should work. I did let the DA stand over night on 4 valves.
 

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Discussion Starter #18
Hmm, maybe a bad gun... hope you had success with the others then. I had major fail myself today... was replacing shocks and the damn shop who had installed the old ones used an impact gun to tighten the swaybar endlinks...and the shock fork... so I am SOL. I even bought an impact gun to try and remove with zero success
 

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Where did you get the walnut media from? In OP's notes he states "HF has a different categorization than other places for the grit on the media" so I wonder if you have a particle size that is not compatible with the gun?
I got the fine grit walnut media, but to me looked like it was on the course side. It worked well if you have a good media blaster!! LOL

Everything went well after I got a better media blaster from HF. Here are some pics of the valves. First pics is the before process of 1 valves, and the next pic is during the cleaning process on one valve. I totally forgot to take some pics of them all cleaned up. All I can say that there was a lot of build-up on them.
 

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First, nice write up!!!

Second, has anyone ever dyno'd before and after a valve cleaning? I wonder how much power loss we have after x miles?

Can't wait to try this out! Thanks again!
 
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