Hey, i have a 1999 F-150 Supercab with the 5.4L V8 with 45,000 miles. Two of the coils were already replaced, #1 and #4. #4 was replaced because of the leaking heater core hose right above it. I don't know why #1 broke. They are the old style coils with contacts, no springs around the connection. The two new ones are the new design. It feels like some cylinders are firing better than others, and there is a lack of power. Should I swap the rest out as well? Are there any aftermarket solutions to this problem?
Can I test if all coils are firing equally?

Thanks for your help

 

Pretty much the only thing you can do is do an ohm test on each coil and see if they're in specs. You may want to think about changing plugs as well.

 

What's that about different contacts? Mine is a '97, and I've only had to replace the #4 coil due to the "standard issue", but when I changed the plugs @ 67K, all my coils had the "spring" type of contact on them........

 

How do I do an ohm test?

Hey, Mitch, the coil I pulled out of my engine had no spring around the connection between the coil and plug. It was just two metal surfaces contacting each other. The new coil had a spring around the connection area. The spring actually wraps around the sprark plug. I've seen other older coils with the same springless design. The older coils were sort of gray on top. The newer ones are shiny black. I could be wrong but I'm pretty sure they changed the design.

Thanks