01 F150 4.6l. Started to missfire, engine light came on, checked the codes missfire cylinder 4. Changed the plug and it went away for about two days. Started to miss on the way home from work and then went away and hasn't come back yet after driving for another two hours. Could it be my injectors, coil, any suggetions ? Thanks

 

How many miles?

 

only 13,000 on a new motor. plugs were changed with the swap but nothing else.
110,000 on the rest of the truck.

 

I would try replacing the coil....After my spark plug blew out I never replaced that coil, which had some wear from the blow by for the last 10000 miles. A few weeks ago I noticed it missing once in a while so I replaced the coil and it went away. I know thats not your situation, but I'd try the coil. Hopefully it goes away.

 

redd01 , with a new motor you definetly do not want a week ingnition - those coils are prolly tired and wore- type "Misfire" in the search this forum area. You can get all 8 new for the the same price as two purchased normally, you'll want to keep your motors integrity. Usually when one goes bad it's a sign that there all week.

jbrew

 

Check your plug wires. I had the same thing happen to mine and it had a plug wire that was arcing. They were not very old wires. In the dark with the hood up I could see the wire arcing. Good Luck!!

 

He doesn't have plug wires lol.

He has COP's

 

Yea i was looking in the direction of replacing the coils. Thanks! I'll let you know how it turns out.

 

Yeah , I would replace them in your case. Think you'll notice that it performs better - like it should anyway.

Good Luck!

 

Here's the Link , people are having a hard time finding it -


Kevins the owner of Global Automotive - When you order
your COP's write him an email or call - specifi the
plugs you want or you'll get the wrong ones. That's if you get the kit.

http://cgi.ebay.com/ebaymotors/NEW-F...temZ8069960486

 

Thanks jbrew!

 

No prob.

 

I didn't know the 2001 4.6's had COP's?

 

I know all 2001's did. I 'm not sure about 2000's though , can't remember lol