Cylinder #1 is throwing the code P0316 & P0301. I changed the plug and the plug wire already and it still misses. The problem just cropped up yesterday and any input would be greatly appreciated, thanks. The engine has approximately 62K on it and it's 2002 6 cylinder Mustang 3.8L

 

I have had this same problem & have changed everything.....Also, mine is intermittent? I don't have a clue?
5.4 2001 supercrew

 

Um, what are we working on?

 

2002 6 cylinder Mustang I think it's a 3.8L

 

I've seen EGR problems cause misfires in split port motors like the 3.8 and 4.2; might have an injector fault too, disconnect the injector and see if your misfire changes any.

 

Disconnecting the injector didn’t make any change; it’s still a dead miss. What about spark? I don’t think it’s been determined for sure that spark is to the wire, going to check for that

could the coil pack be bad?

update edit
Checked for spark with a spark plug wire tester and had spark. All the wires were good

 

Since you have spark and the fuel injector made no difference, I'd say you have either a dead injector, PCM (injector driver), or a valve hung open.

See if you can get a noid to the injector connector to check for injector signal. Measure the injector coil reistance to see if it is open or is shorted to ground.

Check engine compression to see if the valves are operating correctly.

Steve

 

It ended up being a bad coil pack. We bought one for $75 bucks and it solved the problem. Apparently, a spark plug wire tester only checks the wire and doesn’t guarantee the plug itself is firing. Today I had my son (it’s his Mustang) pull the plug and we tested it the old fashion way, cranking the engine over with the plug out looking for spark, well there wasn’t any, no spark. We checked another plug in the same old fashion way and found spark so we went and bought a coil pack and all is well. Thanks guys for your input; all information and different possibilities are invaluable when you’re fishing for a fix as we were