Yesterday when I started my 01 CL type-s it made this strange knocking noise which sounded like it was coming from under the glove box. After a couple of minutes the knocking stops. I have heard it a few times while driving and seems to be happening more often. I have no check eng lights or codes. It doesn't sound like an engine knocking but more like an emissions problem. Any Ideas?

 

I'd say your motor mounts are gone.

 

had them replaced already...different kind of sound. Its more like a steady knock,clicking, or thump for a minute or so with no change at higher or lower RPM.

 

AC on or off? Does it change with that?
There's only the blower motor & the cabin air filters that are under the glove box.
Check you passenger strut, & also inspect the suspension.

 

does it with AC on and off. Its nothing with the suspension because it does it when the car is in park and not moving. Could the cabin air filter cause this noise?

 

Loose cat heat shield? Stumped cause that's all that would make noise in that area of the car.
Try to get under the car with some help to see exactly where it's coming from.

 

will do Thanks!

 

this AM I started car and turned on defroster. soon as the windshield was clear I turned it back to auto air and then I heard the popping noise. So I repeated the above and got it to pop again. Any Ideas?

 

Possible air in your radiator? Im reaching here, but it's possible if there's air in your system if could pop as it goes through.

 

No that has nothing to do with it.

Maybe your blend door, or something with the climate system. You should take the glove box out & inspect the system. Take out your cabin filters & check those replace if needed. There's a DIY for that with pics & details in the FAQ.