B88

Hi.
I've a delsol with a d16z6 engine, i's covered just 96000km and I've noticed it has a little vibration when running at idle speed.

The rpm doesn't bounce, it's a very light vibration. I'm sure that a person who's not used to the car won't notice it.

I've changed fuel filter and sparkplugs (original NGK ref) but it didn't solve the "problem". Vlave clearence has been checked 1000km ago too.

When I slightly depress the accelerator pedal the problem is gone and it revs and runs normal.

Does anyone knows what is it?

Thanks for the help!