cylinder 1 misfire detected after putting NEW ENGINE!

[expyguy]

what's up guys,

So... after having put new engine in my 2005, 5.4L its reading code as cylinder 1 misfire detected under obd 2.
I know my cat went bad, and I took it out just to see how it would run, and I was wondering if that might be it or not but shouldn't it say random misfire detected in that case? it run nice time to time and it would bog down on me if I am driving on cruise specially up the hill.
any advice guys?
My first time posting a thread...
Thank you guys for taking a time to read...

 

[Stoned06]

The COP (Coil on Plug) can be bad out of the box if new, but unlikely. Did you use new ones, or the old ones? I would change the plug and cop and see if that helps. Also, check the electrical connector for the COP and see if it is properly connected, and not crimped.

 

[maverick]

Cops seem to be the problem. Possibly loose or a broken mount. I found a broken one on mine today in fact and I had the exact same symptoms you have described.

 

[expyguy]

Thanks for posts guys.
plugs were put in brand new.
I just had cop 1 and still doing the same thing.
Could it be o2 sensor or could it be cat ?
But if it was the o2 shouldnt it say random misfire detected instead of cylinder one misfire detected?
I don't know what to do...