Quote Originally Posted by matbor
I wonder if these products actually work and whether they cause any other damage in the process !!
I know the Subaru one works. It won't cause damage (Genuine product, I think they wouldn't sell it if it caused damage) and you can see and feel the difference. I use it to clean my throttle body and my fast idle valve.

Subaru introduced it when early Libertys started having pinging issues. Driven gently they can suffer from carbon build ups, which create hotspots that cause pinging (pre ignition). The cleaner helps to eliminate the carbon build ups.