Well 2.5 years later I finally bought one, yesterday in fact! I ended up not being convinced I could have one as my only car as I needed a bit of practicality so I've waited until I can afford to run two cars, so now it's my weekend/toy car Its a 2004 660 with 32k miles, 1 owner! FSH from a Daihatsu dealership until they closed and then serviced at the same garage when they went independent. The leading edge of the bonnet in the corners have some bubbling and the sills have been welded at the back but other than that I can't see any rust and I've had a good poke around. So far I've only driven it the 40 mile motorway journey home, its loud, louder than I was expecting the roof seems to rattle around all over the shop, I've previously had a soft top Punto (1994 so no spring chicken) and it was substantially quieter than little Copen! The owner tells me its unmodified but the BOV is very loud, this is my 3rd turbo charged car and I've had cars with open BOVs before but even they were quieter than this, what am I looking for under the bonnet to see if its the standard one? The suspension is rock hard but I did expect that, the steering is more direct than any of the other 9 cars I've owned to date so its fun to dart around!
Yay! You got one, enjoy every minute. Sure someone will be along to help with the technical stuff soon
The BOV is more of a recirculation valve as it does not blow off any air into the atmosphere, so it should be fairly quiet however copens don't have that much noise insulation so it can still be heard a little more than other cars (especially with the roof off) Below is a picture of the factory system. To remove the engine cover remove the 2 bolts and pull up from the back as marked red on the picture. The blue is the factory system. The green shows the pipes that connects it to the intake and air box. Check these areas for leaks as air escaping here will cause a louder noise. It could be that rubber hoses have begin to harden and cracked or a clamp has worked loose.
Thanks AFR0N, just what I needed. Had a look and everything seemed standard and connected Until i noticed this, That'll most certainly be the cause of the noise then, is that not the valve cover breather? Would would cause that to pop off, I'm guessing boost shouldn't be going that way?
