I don't even know if this is a problem. I had this ever since I gotten the car.
Whenever I am stopped with engine turned on (at 1st gear or Park) I feel these strange irregular vibrations coming from underneath the car. The vibrations feel the same from the driver and the passenger seats so it must be somewhere in the center underneath the car. I cannot hear them and I can only feel them if my feet are on the floor of the car. Once I start driving these small vibrations dissapear and it is a smooth drive from there.

So I was just wondering if this a normal side-effect of a the engine idling or this is somehow related to the whole driveline vibration thing that some people feel around 50-60mph? Other than these small vibrations my car is smooth as silk otherwise.

 

It's not driveline, the car has to be moving for that.

According to the manual, rought idle is from the anti pollution stuff.

Are you using the correct octane gas?

 

I woundn't call it "rough", it just vibrates more than I was used to. I guess pleasing those EPA terrorists would be a good answer. I do believe the overall idle RPM are higher than in old Prelude. I guess it makes sense if it's infact true that lower RPMs somehow produce more polutants (anyone know for sure?)

 

Slava - Is your A/C on? when the compressor kicks in you'll feel a bit of a vibration through the steering wheel at idle.

 

Nope, I know about the A/C. I actually normally turn it off when I am at a stop light and turn it back on when I start moving.

I believe the vibrations are connected to idle RPMs. When my engine is cold and the idle RPMs are higher than normal, so do the vibrations become "rougher". Again, I do not think this is a problem if someone could confirm they get the same issue in their car.

But if everyone's car is completely smooth at idle then mine does have an issue.