on my 93 wrx the vents are blocked off is there a reason for this? can u take the blanking plates off and will it make a differance

 

They're all like that!
If you take them off, you'might' get water in the electrics, but then again you might not!

 

blocked off vents is normal of all cars. You can take them off if you want but as RON said, water might get in.

I've got the plates off mine, plus I've added some funky little scoops (courtesy of Stuart Knight) to cover the 'holes' take a look at