I did this job myself and I’d just like to post a few tips on cleaning methods, as I think all other pertinent info has been covered. NY07RS4’s tips were quite helpful in some of the steps of this job: http://audirevolution.net/forum/index.php?topic=439.0 . I’m confident that I can now do this job in 1/4 of the time it took me the first time around.
I tried several cleaning methods including BG’s cleaning kit, walnut shell blasting, and basic scraping/brushing with a little brake cleaner.
BG FSI cleaning kit
http://i.imgur.com/PuwtqZT.jpg
BG’s kit comes with three bottles of liquid(their 44K fuel system cleaner (PN 208), PNs 271 & 272), a bunch of zip ties tied together, some wooden picks, and a steel brush pipe cleaner. The two liquids used to soak the valves do a sufficient job of softening the carbon deposits up, but I found that the bulk of the carbon deposits were malleable enough without any liquid treatment. BG’s kit was a waste of money in my opinion. The steel brush pipe cleaner lasted about one valve scraping. The wooden picks were pretty useful, but thickness varies and some will crack/break under normal pressure. I broke the last one during the last valve scraping and at that point I had found better tools. The bundle of zip ties is GREAT for the initial breakup of carbon deposits, but its nothing that cant be gently performed with a flathead screwdriver.
Walnut shell blasting
I was really excited to use the harbor freight media blaster along with the walnut shells I had just purchased. Initially I wanted to purchase http://www.harborfreight.com/20-lb-pressurized-abrasive-blaster-68994.html but they were out of stock so I went with http://www.harborfreight.com/portable-abrasive-blaster-kit-37025.html . This didn’t do much for the second set of valves I cleaned. Perhaps it just wasn’t powerful enough. I ran my air compressor between 90-100 PSI, which should have been enough. I would like to try this again with a better blaster and a specialized tool for our valves like BMW has.
Manual scraping/brushing with a little brake cleaner
In my opinion, the most effective and easiest method of cleaning was to start with the bundle of zip ties and jam them repeatedly into the valves. This effectively broke up the large chunks of carbon on the valve stem and valve walls. After that I scraped the valve walls and stem gently with a medium sized flathead screwdriver. I then pulled out any carbon that had come loose at this point. I used small phillips screwdriver that I bent the tip of so it was hooked to scrape around the bottom of the valve. After picking that stuff out I used a cylindrical steel wire brush, which can be found in the plumbing section of most hardware stores, to brush the remaining carbon off of the valve walls and stem. Please note, I inserted a rubber vacuum cap onto the end of the steel wire brush so the stem did not score the valve walls. You should be able to use a shop vac to extract the remaining carbon particles and dust. Spray down the valve with enough brake cleaner to cover the the bottom of the valve. Let it soak while you move on to the next valves. After you finish the last valve let them all sit for another 15-30 minutes then twist up some paper towels and jam them into the valves to soak up the brake cleaner. Leave the paper towels for about 15 minutes and remove them. You will have some brittle carbon remaining at the bottom of the valves that can be easily scraped and vacuumed out.
Here are the before and after videos - sorry for the vertical format:
Before: https://www.youtube.com/watch?v=Gc3gNn2ed8E
After: https://www.youtube.com/watch?v=aYRpDgrU430
Please reply with any questions or comments. If anyone would like the full PDF of the IM removal procedure from the bentley manual I will post it.
