3V Chasing a Miss after Spark Plugs

[dross93ranger]

Me and a friend who is a diesel mechanic just changed the spark plugs in my 2005 Expedition with the 5.4L 3V motor (65k miles). We changed them with Autolite H1 spark plugs. Before they were changed there was a miss between 40-50mph. After completing the spark plugs there are codes for misfire on cylinders 2 and 8. We have tried new coil packs, switching around spark plugs ect...

What else is there to try? New boots were installed as well, any help would be appreciated.

BTW I believe this is a dead miss...it has no power whatsoever now.

 

[dross93ranger]

Found the issue...took it all apart and the porcelain was loose in a couple of the plugs. I will never order my plugs online again, I guess it happened in shipping.

 

[rburch]

Keep us up to date on the plugs! These 5.4 usually reject plugs that arent Motorcraft!

 

[dross93ranger]

After 2 days the Expedition is running like a top with the Autolite H1 plugs.

 

[ZombieSoldier]

i had all mine replaced by ford, and yet it still has the miss. thats after replacing all COP's as well. I am about to go balls deep in this ***** soon.

 

[Mikes05expy]

i had all mine replaced by ford, and yet it still has the miss. thats after replacing all COP's as well. I am about to go balls deep in this ***** soon.

I had a miss in my crown vic that I couldn't find then ended up blowing a plug out. I had the plug fixed, replaced the coil that it destroyed then had to have a new pigtail put on cuz it melted the wires, the guy doing it chased it into the harness about a foot and found two breaks in one of the wires. Once that was fixed it ran like a ***** ape.

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