Can anyone help? I have a 2001 f-150 4x4 4.6l. How can i identify which coil is bad. I'm not having any luck by unplugging each one. I notice a change in the idle with each one when i do that. Can Autozone tell with there computer? I'm trying not to go back to ford if i can help it.
thanks

 

Is your CEL on? If so, have Autozone, or whoever, read the code. If it is a misfire, it will tell which cylinder.

 

thanks
i'll go down to autozone