coil packs

New to the forum, trying to find a particularly elusive problem. Yesterday I changed the oil on my 1st Gen MS3 (2012 engine in it) and about 30 minutes later when I was merging onto the highway it lost power and started misfiring. Whenever I go past a certain throttle position it started...

Okay, I have done a lot of research and posted on multiple forums but I am stuck. Preface: 2007 Stock Mazdaspeed3 with short ram intake. Bought at 108,000 miles from the original owner, currently has 120,000 on the clock. The Head gasket blew and burnt a valve at 112,000 miles. Replaced the...