MY 2001 4.2l was running rough so i replaced plugs and coil and didnt fix it then the code read up misfire #1 #4 #6 and egr so i replaced the egr and now it idles but still no fire in those cyclnders any ideas?? help thanks brian

 

plug wires?

 

also did them too i am starting to think about the iac or knock sensor ???

 

egr ports in lower manifold could be clogged up.