Re: coils/pressure reads
If you have good spark to all cylinders then your coils are fine. As to the difference in compression it could be a stuck ring, scored cylinder, broken ring, etc... It would be nice to know what engine that we are talking about. You might pull the head and have a look see. Should tell you a lot. Make sure that you buy a new head gasket and don't reuse the old one no matter how good it looks.