I have a 2004 rx8 gt mt, car idles fine runs ok untill about 5kup its a flutter noise, i really hate the fact that i cant figure it out, no one can. I Have checked all plugs wires coils all to seem to be working and ok, I have an aem cai and a turboxs full exhaust , i recently found a hose disconnected which seemed to have went to my ssv or apv not sure one of the other, ( right behind the passenger side wheel well) I have plugged it in, My Motor has 8k on it from Mazda This is my 3rd reman and im very upset about how things are playing out. Here are some clips of the flutter i am getting please watch and help if you can.


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this is also an unkown noise in the cabin, sounds to me as if a motor is trying to turn over but wont. so i thought maybe the motor to the APV is gone.

 

Your first video, at the end, shows a flashing CEL. That is your ECU detecting misfires.

I'd recommend keeping an eye on this thread, since we are trying to solve that, and it sounds the same: https://www.rx8club.com/series-ii-te...9/#post4304602

Except his is only the upper range, not lower range as well.

 

Will do , misfire Is on rear rotor (p0302) also I am receiving p0410

 

I posted over there, but his issue appears to be a vacuum leak. Can you pull an ODB2 log at idle, at least 10 seconds? It would confirm the same thing, though i'd say that you have two leaks.

 

They move the coils from your old engine to the reman. How old are the coils?