I have a 2004 rx8 m/t have a knocking sound coming frome the motor coils check out ok plugs are only a month old just change the oil compresion is good also and no random vibrations like a motor mount is bad been driving me nuts for a month now any help would be greatly appreciated

 

When does it do it?

Does it sound like a rotating knock?

Is it RPM dependant?

 

Only when it fully warms up and mostly here it at idle rpm once I apply throttle disappears and hes it does sound like a rotary knock could synthetic oil cause the noise

 

Go put your finger on the rod coming out of the end your ssv valve. I'm betting you have some play where that rod connects to the lever that open and closes that valve. Spring is probably weak and the end of that shaft is wore causing the clicking or knocking sound you here.

 

I did that last night the knock I'm hearing is much slower like a rod is knocking you are right about the spring

 

I have had a similar sound at idle. It happens only below 1000rpm when the engine is fully warm, its rpm related. I had this in my old engine, a cheap rebuild came up from a failed project so I put that in and the new engine is now knocking. Sounds just like a bearing or rod knock on a piston.

Using an automotive stethoscope, its coming from the RHD of engine around the Alternator/OMP/engine mount area.

I have replaced all igniton components, pulleys/belts, alternator, SSV and OMP to no avail. I put my old OEM mounts back in and the noise reduced alot, but is still there. Oil drain and filter are free of metal.

Im wondering if its the pulsation dampener or primary injectors knocking at idle rpms. Apart from my Sohn, there aren't many other possibilities left. Has anyone experienced a knocking sound from these components?

Hope this is of some benefit to you.

EDIT: Just saw the date of the last post haha. Did you ever resolve your issue Cameronlemay?