Coil Packs, Wire Set & Plugs????

[JMKiser]

I have 1999 F-150 4X4 with a 4.6L at 116,000 miles. At what mileage “should” the two coil pack, plug wire set and plugs be replaced?


John from Alaska….

[Manipulator]

I wouldn't worry about it unless you are developing some misfires. The boot that goes from the coil to the plug just has a spring in it that makes the connections. Can't see much going wrong with that. Then again I'm probably talkin too soon. I'm not sure if the 99' has the same setup as far as ignition as my 03' 5.4L. I know on mine Ford recommends 100K for spark plug change. I think this is too long, I changed mine at 69K and they were ready.

[galaxie641]

HE has the older coil packs not the COP's. I wouldn't replace the actual packs until there is a problem. I replace plugs and wires around 60K-70K. Remember torque the plugs properly to around 15lb-ft and use a dab on anti seize on them.

[LxMan1]

+1

Use Motorcraft plugs and wires for best results.
The coil packs will last indefinitely. I would replace them until one fails.