hello, I am new to the forum. thanks in advance to any and all that reply.
I have a 2002 F-150 super crew with 4.6 V-8 Triton.
At 69,500 miles I had a misfire (no code at this time). I did a tune up (pulgs, coil wire and boots, fuel filter, oil, and oil filter, pcv valve, and air filter. This did not correct problem. at 69,600 miles the service engine light came on. I went to Auto Zone they coded it as P0316, P0308. I looked this up it the 316 was a misfire in the first 1,000 revolutions, and 308 was cylinder 8. With the recent tune up I figured it to be the cop on cylinder 8. Replaced it service engine light off, engine runs like new. Now at 70,006 miles the truck is running hessitant again, and the service engine light comes on same codes P0316, P0308. I am at a total loss, any ideas?

 

02 4.6 didnt have wires. what brand plugs did you use? did you use dielctric grease inside the coil boots? you may need new coils. you can get a full set of 8 off ebay for 70-80 bucks from global or uneek. just type dg508 in the search bar.

 

Motorcraft plugs, and correct not wires but rather the spring from coil to plug. No I did not replace all coils at the time of tune up. Yes I used dielectric grease on the spring to plug, and coil connection.
The new misfire code on cylinder #8 is the one I did replace the coil on. So the misfire coil has less than 400 miles on it.

 

The dielectric grease should not be used on the actual electrical contacts. The spring itself and the terminal on top of the plug should not be greased. The grease is used to lubricate the boots and to help waterproof the boot/plug interface.

 

Thanks,
I applied the dielectric grease as per instructions with the CoP (autozone) I bought.
I will be trouble shooting starting with #8.

 

I get folks with skips all the time with the knockoff coil packs from Autozone, Advance, Napa, O'Reilly's , etc.

Do yourself a favor and get a Genuine Motorcraft coil pack and end your woes

FordMasterTech

 

Thanks for the responses I'll know better if their is a next time.