Walnut Blasting vs. Chemical Carbon Cleaning?


New member
Dude, I'd go to a service station with a problem like that. I think it's hard to solve it on your own, there are a lot of factors to consider. I was recently at a family dinner at my brother's house. We were sitting at his house and everyone got hot. We asked him to turn on the air conditioner, and it gave off such a horrible smell, like a football player hasn't changed his socks in a year. Thankfully the weather was nice, and we moved to the terrace. He then tried to solve the problem himself, but it didn't work. He had to use a cheap aircon chemical wash singapore. That's why I'm sure you should leave it to a professional.
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2007 MKV GTI
Media blasting, or a manual scrubbing after soaking are the best options for a complete cleaning.
I use a solution blow-by, but only to keep them somewhat clean in between the more thorough manual cleanings. The two after "solution blow-by" pics below show it keeps them relatively free of major clumpy build-up, but they still show deposits on them.
Here's a couple of pics; one to show valves after a manual cleaning__and two after pics of my blow-by in between manual cleanings;

Manual cleaning results;
valves after1.png

In between using my solution and the Blow-by method;

...And a fuzzy close-up;
valves after og.jpg


Passed Driver's Ed
Chemicals dumped in through the intake do nothing. The carbon is baked on, hard. You can soak the ports and valves in 'Carbon off' overnight and still be there with picks and drill brushes for hours, I've done it.

Walnut blasting is 10-15 seconds per port once the intake is off, and nowhere near as messy. No GDI engine maker has come up with a solution other than media blasting. They have tried every other method out there, and they don't work. The European MK7 Golf R has 4 additional port injectors to help combat the problem. VW claim the move was for emissions/top end power but it's BS. They don't want to pay techs to clean engines, or admit their oversight of PCV vapours/exhaust reversion gumming up the valves. Washing the valves with gas is the only way to keep them clean in the long term, as per, erm, port injection from decades ago.

FWIW, carbon build up isn't an issue until it gets to the point where it obstructs the stratified injection air tumble, which causes warm-up misfires, and only at idle. Until that point, just ignore it and get on with your life. It's only the naturally aspirated FSI engines that suffer power losses from carbon obstruction. Turboed FSIs will shove the air in regardless and make the same power.
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