X-1R pouring in my Subaru 97 Legacy 2.0lt, non turbo wagon

My Subaru 97 Legacy 2.0lt, non turbo wagon has developed the most common for Subaru knock noise before warming up the engine. Once warmed up the noise is gone. So now trying the X-1R Engine treatment

[@mikehaw32]

Any update? Whats the result?

[@richardmarcott4343]

Sounds like it made motor quit running!!

[@beasieras5553]

It can be used on diesel engine?

[@swordsmanink]

Please check manufacturer Website

[@tac13001]

Did you put it in your diesel?

[@JyunCheng]

Yes it can.