I had the knocking issue before, upon start up, right after I got my MCS'05. I stuck with high octane gas and the issue has gone away. Now on my 17 thousand mile mark I get no noise, but a tach that goes below 500rpm, seems to wake up and go over 1200rpm only to go back down, like a see-saw. What gives? Is it tuneup time already?
Florida Dan

 

Sounds like the yo-yo

You might be in for a trip to the dealer - if it is the yo-yo they have tried to fix the problem with new programs for the ECU -- none of them have been a sure fire fix.

I have heard that the JCW reflash will help ( if you have the right mods - 15% SC pulley ) or I found unichip on sale on ebay and that seemed to cure my 04MCS yo-yo troubles.

Good luck

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