i have a 93 wrx had it a while, comin home from work steady driving wed night there was a slight missfire at low revs 2000rpm so kept the journey home slow.Had a look round under bonnet so took plugs out and noticed oil all the way up the thread to washer and porcalain cracked in 3places and still have missfire after changing plug,is this possibly the end of engine .The plug was the drivers side at bulkhead ,any info would be much appreciated thanks.