If that is definitely your problem, I would not continue driving it like that if it were mine because yes, this will not do anything but get worse! Take the head to a machine shop to check for a warped deck. while your at it, have them look it over and make any necessary repairs, valve job ....etc.

I did a cylinder head overhaul on mine when it was removed including a valve job and now it runs great! One thing I was told to do which is not always clear or in the book is to recheck the head bolt torque after 1000 miles of driving. Follow the same pattern depicted in the directions and you should be fine.