97' sierra K1500. 5.7 cylinder #4 wont fire

[jeradciesielski]

My truck's check engine light came on so i had a local mechanic shot diagnose it. They told be Cylinder #4 was missing a lot and something about that being just at idle rpms. And cylinder #3 was missing a tad to. Anyone have any idea what it could be? valve maybe? idk.. And i already checked basic stuff like plug and wires.. HELP!

[RyanbabZ71]

closing topic, no need for the same topic in multiple locations. Please see the 1960-1999 section if you have an answer