I just changed all my plugs and coils on my 2007 5.4 with 100000k on Mon. I unplugged the battery and two hoses to make room. Got everything swapped and put back together and fired it up ran good and idled good so i shut it off cleaned up and started driving back home (across the street). By the time i got home it barely would move or stay running. So i put in a new mafs and cleaned the tb and that helped but it still idle rough and drives like there's a misfire and kind of bucks a little bit. I don't know what to do I'm about to push it off a cliff

 

Coil pack!

 

8 new ones on there and above 2500 rpms rev is smooth as butter

 

yah now idles and runs like crap too feels low on power?

 

Stupid reply but maybe one of the plugs isnt in all the way or maybe one of the plugs is faulty from the factory?

 

Exactly

 

The coil packs are sensitive from what I've heard. Maybe you damaged them. Or just a misfire from a faulty plug. No check engine light? Codes?

 

No codes at all. I heard something about an ecm relearn after disconnecting the battery but it's been 4 days

 

I had a buddy who got a bad coil pack from right out of the box.

 

Wouldn't that throw codes tho