RafaS2K

Hello to everyone. I'm knew to this forum, so pictures of my recently bought S2k will come.

I need some help with a very strange rattle I've found sounding like inside tha gas tank (fuel pump?) However, car runs fine, starts inmediatley when cold, iddle is perfect... and plus only sounds after 5 minutes left on iddle without reving at all. Once you press the accelerator, either before or during the noise I mention, it will disappear.

I've already jacked the car and haven't seen any heatshield rattling, or leak in exhaust or gas pipes.

I have uploaded a video so that it can be listened. As said before, this happened after 5 minutes since first start, with the car not moving at all.

Some sort of light towards this problem will be appreciated. Thanks!

My link

Reckon

Interesting noise...it sounds like like a loose cap or even the exhaust pipe hitting on something. Not sure what it could be...is your exhaust secure and not hitting againt anything? Do you know of anything that might have fallen in the back of the cabin by the fuel tank? Since you just bought the car it might have been something the past owner did.

RafaS2K

We checked all the exhaust pipes and everything was ok. Not sure it would be something that could have fallen, as in such case the rattle should be there all the time.
It's something really strange, especially beacuse the sound disappears as soon as I rev the car a little bit, and it keeps aways until the next cold start.
Could it be the fuel pump causing caivtation? or struggling to get fuel?... However, as said before, the car iddles and runs perfectly, so still no idea...
The car is booked at Honda dealer next tuesday, but if I could give them some clues, I could save some €€€€ XD

s2cho

DONT TAKE IT TO THE DEALERSHIP.

I had this problem and i struggled for about a year until i did extensive research. This was the biggest pain in the butt i ever dealt with.

This is your problem 90%

https://www.s2ki.com/s2000/topic/549...#entry12041341

https://www.s2ki.com/s2000/topic/365.../#entry7156985

its the fuel regulator cap. it has 3 bolts and it will not tighten. just undo the three screws and throw some tissue or dynamat in it. it solves the rattle right away. or even better yet start the car and get it to when it rattles and hold the regulator cap and see if the rattle goes away.

For the other 10% its the fuel neck that has gotten loose. check these two things before you go to the dealership and spend some money.

RafaS2K

Thanks for you help. I have checked what S2cho said and nothing changed...the rattle is still there. Do I have to unscrew the three bolts to check the rattle inside that cap? Or should it disappear by holding it in place with my hand?
I made another check under the car and noticed that the black cilinder where the fuel filter is vibrates with the rattle and stops vibrating when the rattle disappears too, although the sound comes a bit more above this part.

s2cho

remove the 3 bolts and start holding part by part until you find it... if its not there its probably the fuel neck. open the gas lid, open the gas cap and see if the fuel neck is vibrating when the rattle is present,