Q: PO305 error code on 1999 Jeep Cherokee

Rookie cbe0621eac06868b3efe0d8d1d3611e23c60d3114864ea2ec19a68cfbd3eebab
Jeep has started to idle rough. OBDII code reader says PO305 (#5 cylinder misfire). Changed plug and wire, no help. Problem only at idle.
(1) Answer
(1) Comments
check the injector and do a compression test. lots of problems with exhaust valve seats going bad.