I'm thinking of trying this on my Corolla; I recently used Techron and Seafoam through the PCV hose with fairly dramatic positive results. However, upon installing new spark plugs, I can clearly see the piston tops still have what looks like a soft/oily/shiny looking deposit layer. The car still has a very slight ping under hard acceleration that has mostly been solved with the Techron/Seafoam, so I thought I'd try the water decarb method for the heck of it. I was planning to do it through the PCV line since it looks like it evenly feeds all 4 cylinders. However, I read a few posts where people had problems messing up the MAP or other sensors using a vacuum line to feed water in. Is this really a problem? Has anyone successfully used the PCV line to do a water decarb, or should I just spray directly into the throttle body? I'm planning to use a spray bottle with hot water with the engine hot and running at 1500 rpms.
Thanks
Thanks
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