Oh OK I see what you are sayin, you don't want to void the warranty. Yes call em & go from there. post what they have to say. I would drill another hole in a cap as that is likely what they might ask, is how far off is it? EDIT You wouldn't want to send it in just to find out what you can find out yourself (how far RP is off). One other thing I would do now is bump up the timing/RPM to where it was acting up before (with the can capped) to see if it strickly a RP issue & not timing. You would need a dialback.