My pampera rattles too and it is kind of similar. Happens at very low rpms or on very hard acceleration. But I think the cause of my rattle is either the chain slapping or something to do with the exhaust. Are you sure the noise is coming from the engine? Maybe the spring on the exhaust header is coming into contact with the pipe itself? I had a random spring on there and it was causing some noise aswell.
YT kanali j?rgi sa vist eestlane ?ldse