Our car just developed a loud tap or rattle in 2nd and third gears for just a second around 4500 to 5500 rpm at anything more than 75% throttle. The engine has roughly 16000 miles on it since assembly. It does not sound like valve noise that you get after say putting in too low of octane. It is louder. It sounds like it is actually in the dash, right above the radio.
The power has not dropped off that I can tell and the engine at any other rpm or load sounds perfect other than the slight sewing machine sound you would expect from the cam. I can't hear of feel a miss and the idle is also unchanged.
Anyone know what it could be? Clutch chatter? I thought maybe the pcv valve had popped out and was vibrating against the firewall because that's exactly what it sounded like but it is still properly seated.
Any thoughts would be appreciated... JernJen

 

It could be clutch.. but I'd probably start looking around in/under/behind your dash.

 

would a clutch have a plastic to plastic sound/ I had a bottle cap in the storage bin where the tcs button normally is and thought that was it but was wrong. It sounded just like that cap was vibrating though.

 

I think a clutch would be a heavier vibration than that. It probably is just some plastic.

 

I hope you're right. Thanks for your time. Jerry

 

Those are sometimes tough to find because an underhood rattle of something connected to the interior - like accelerator cables, a/c hoses etc. can often sound like they are in the dash. Take your time, to listen, poke around, check things, move things that look close, check your heat shields undreneath, etc.

 

Thank you. I'll get to diggin'. I was worried that it was mechanical and you know how scary it is to worry about 400+ horses limping towards a powder keg!