At 4,000 rpm, there is a loud 'rasping' from under the car. It sounds like something is vibrating, like an exhaust nut / bolt, or a sheet metal plate of some description.

Before I take it for inspection, does anyone know of such a noise being commonplace on the S2000? If so what is it ?

 

I'll have a fiver on the Cat heat shield.

I'll go an extra two quid on it being 2 of the bolts missing...

 

an easy fix at a local garage?

 

I can't remember if they are captive nuts on the heat sheild but I'm guessing they'll have rusted and snapped.

You could always get em to just remove it totally... that's only 5 mins work.

 

Clutch buzz?

 

Could well be the cat itself.

 

That was my first thought. Inside the CAT are two sections of honeycombe which are bonded in place. If the front one breaks loose it will knock against the O2 sensor. What you could do is either take the CAT off and shake it, or remove the O2 sensor and see if you can move the honeycombe section with your finger. That's what was causing a rattle on my car.

 

I have this as well, doesnt bother me too much but I put it down to clutch buzz
be good if it was just a heat shield

any updates on yours BigDogsWang?

 

I'll see GaryB's fiver and raise you a Tenner on Heat Shield.

Just had mine fixed and I had 4 bolts missing. Here's my very boring thread about it
https://www.s2ki.com/s2000/topic/894...-rattle-fixed/

Being lazy I took it to Honda to look at, so got charged half an hour's labour to diagnose and fix. I'm sure it didn't take that long but I think that is the minimum they charge for diagnosis.