I'm not sure if its a vacuum leak or not, but when I listen closely to my engine idling, I hear a hissing noise coming from the attachment of the air cleaner hose. Is this normal? I've had a problem with low idle and misfiring for a little while but I actually made a big improvement with a recent tune-up (doesn't misfire anymore at least). I don't see any cracks or anything in the air cleaner hose, so if it ISN'T normal I would assume the attachment is loose/broken.

Also, I notice the distributor is kind of noisy (almost like a rattling spin) when I listen to it. Is it normal for the distributor to make noise like that? Could it just be the normal sound of the rotor spinning? I know the distributor axle can get warped and such, but it doesn't sound THAT bad really.

This is for a 93 Civic DX. I'm kind of **** about it running like new.

 

A lot of aftermarket intake systems like to 'hiss', especially on sohcs. But, ive never owned a stock air cleaner tube