Guys,

My M103 produces pinging sounds when under high load, e.g. passing or hard acceleration. I suspect there's carbon buildup in the combustion chamber and it should be cleaned. Some suggest using water can do the job. They advice to spray water into the throttle body while letting the engine at about 2000rpm.

Has anyone of you done it and what is the result? Does water do any harm to the mechanics of the engine?