I have tried to fix this vechicle myself. I have changed the spark plugs, wires and the igniton coil. It is still missing, jumping, idleing low, and just not running smooth. The four wires that go to the plug that goes into the ignition coil are all hot. I have foune out three are supposed to flash and not sure about the last one. One of the ones that is supposed to flash stays on constant. Is this because of the pcm or a bad wire connection somewhere?

 

This a V6 petrol I take it. Per your change of coil 1 I take it there's 2 coils. Sounds like a coil issue but Idling low ! Does it power ok, if it does could be Lambda.